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29 Mar 2010

Volume 96, Issue 13, Articles (13xxxx)

Issue Cover Spotlight Figure

Appl. Phys. Lett. 96, 133101 (2010); http://dx.doi.org/10.1063/1.3373422 (3 pages)

Shengfei Feng, Xinping Zhang, Hao Wang, Mudi Xin, and Zhenzhen Lu
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Single-defect photonic crystal cavity laser fabricated by a combination of laser holography and focused ion beam lithography

Sungmo Ahn, Sihan Kim, and Heonsu Jeon

Appl. Phys. Lett. 96, 131101 (2010); http://dx.doi.org/10.1063/1.3373527 (3 pages) | Cited 3 times

Online Publication Date: 29 March 2010

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Large-scale, high-throughput fabrication of photonic crystal (PC)-based devices was achieved by using a combination of laser holography (for background PC generation) and focused ion beam lithography (for defect formation). An array of InP-based square-lattice PC lasers with a single air-hole defect was fabricated by this combined lithography. The resultant lasers consistently exhibited two lasing modes, which were identified as quadrupole and dipole modes on the basis of their spectral and polarization properties. The high cavity Q-factor ( ∼ 2200) and low laser threshold ( ∼ 0.25 mW) indicated that the laser quality was comparable to that of the PC lasers formed by electron-beam lithography.
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42.55.Tv Photonic crystal lasers and coherent effects
42.82.Cr Fabrication techniques; lithography, pattern transfer
42.40.-i Holography

Effect of heterointerface polarization charges and well width upon capture and dwell time for electrons and holes above GaInN/GaN quantum wells

Martin F. Schubert and E. Fred Schubert

Appl. Phys. Lett. 96, 131102 (2010); http://dx.doi.org/10.1063/1.3373610 (3 pages) | Cited 7 times

Online Publication Date: 29 March 2010

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The dwell time of electrons and holes above GaInN/GaN quantum wells is calculated using the k⋅p quantum transmitting boundary method. A long dwell time is an indication for high probability of carrier capture by the quantum well. Conversely, a reduced dwell time indicates that the carrier is likely to be coherently transported across the well. It is shown that sheet charges at GaInN/GaN heterointerfaces and a narrow quantum well lead to significant reductions in carrier dwell time. In addition, carrier capture is discussed in terms of a classical model that is consistent with dwell time calculations.
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73.40.Kp III-V semiconductor-to-semiconductor contacts, p-n junctions, and heterojunctions
72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping

Acousto-optically tunable lithium niobate photonic crystal

Nadège Courjal, Sarah Benchabane, Jean Dahdah, Gwenn Ulliac, Yannick Gruson, and Vincent Laude

Appl. Phys. Lett. 96, 131103 (2010); http://dx.doi.org/10.1063/1.3374886 (3 pages) | Cited 6 times

Online Publication Date: 29 March 2010

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We report on an active two-dimensional lithium niobate photonic crystal (PhC) driven by stationary Rayleigh surface acoustic waves. The configuration relies on two interdigital transducers that modulate the refractive index through the acousto-optical effect. Highly efficient, compact acousto-optical PhCs with an active length of only 13 μm and a driving electrical power of 20 mW have been fabricated and characterized. Experiments show that an enhancement factor of the elasto-optical interaction of the order of 61 is obtained thanks to slow light effects in the PhC.
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43.38.Rh Surface acoustic wave transducers
43.38.Fx Piezoelectric and ferroelectric transducers
85.50.-n Dielectric, ferroelectric, and piezoelectric devices
78.20.hb Piezo-optical, elasto-optical, acousto-optical, and photoelastic effects
42.70.Qs Photonic bandgap materials

Role of excited-impurity quasiparticles for amplification of radiation in an erbium-doped glass fiber amplifier

K. F. Renk

Appl. Phys. Lett. 96, 131104 (2010); http://dx.doi.org/10.1063/1.3372630 (3 pages)

Online Publication Date: 30 March 2010

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In this paper, I will show that excited-impurity quasiparticles may play an essential role for the amplification of radiation in an erbium-doped glass fiber amplifier. A quasiparticle consists of an excited state of an erbium ion interacting with other erbium ions and with the thermal bath via phonon-assisted energy transfer processes. The quasiparticles populate energy levels of a quasiband. Fermi’s statistics determines the average occupation numbers of the levels. The quasiparticle model leads to an analytical expression for the gain coefficient of an erbium-doped glass fiber amplifier, or generally, of a fiber amplifier or fiber laser.
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42.55.Wd Fiber lasers
42.60.By Design of specific laser systems

Gain analysis of blue nitride-based lasers by small signal modulation

J. Müller, M. Scheubeck, M. Sabathil, G. Brüderl, D. Dini, S. Tautz, T. Lermer, A. Breidenassel, and S. Lutgen

Appl. Phys. Lett. 96, 131105 (2010); http://dx.doi.org/10.1063/1.3372637 (3 pages)

Online Publication Date: 30 March 2010

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With a small signal frequency-modulation of the driving current, the resonance frequency and the damping factor of the optical output power response of blue nitride-based ridge lasers grown on [0001]-plane gallium-nitride substrates were investigated with a network analyzer setup. From the linear dependence of the squared resonance frequency on the driving current, the gain coefficients of the logarithmic gain model could be extracted being 7680 cm−1 for blue nitride-based lasers. For this purpose, additional parameters such as the carrier density and the confinement factor were assigned by carrier lifetime and quantum efficiency measurements and one dimensional transfer matrix simulations, respectively.
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42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems
02.10.Yn Matrix theory

Wideband Y-splitter and aperture-assisted coupler based on sub-diffraction confined plasmonic slot waveguides

Z. Han, A. Y. Elezzabi, and V. Van

Appl. Phys. Lett. 96, 131106 (2010); http://dx.doi.org/10.1063/1.3374454 (3 pages) | Cited 8 times

Online Publication Date: 30 March 2010

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We theoretically and experimentally investigated compact Y-splitter and aperture-assisted coupler based on subwavelength plasmonic slot waveguides to demonstrate their capabilities for routing light at the nanoscale. The devices were fabricated on a silicon-on-insulator platform and integrated with conventional silicon photonic waveguides which enables efficient light coupling into the nanoscale plasmonic slot channels. The fabricated splitter and coupler structures exhibited wideband operation over the 1510–1630 nm telecommunication wavelength range, making them suitable for use as basic building blocks for light manipulation below the diffraction limit in plasmonic slot waveguides.
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42.79.Gn Optical waveguides and couplers
42.82.-m Integrated optics

Microwave characterization of Purcell enhancement in a microcavity laser

H. W. Then, C. H. Wu, M. Feng, and N. Holonyak

Appl. Phys. Lett. 96, 131107 (2010); http://dx.doi.org/10.1063/1.3377913 (3 pages) | Cited 3 times

Online Publication Date: 31 March 2010

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A sensitive microwave method is described to study the optical frequency response of a microcavity laser, demonstrating that a quantum-well vertical cavity surface-emitting laser ( ∼ 3 μm aperture, ITH = 180 μA) can exhibit almost single mode operation (nearly threshold free), and an electron-hole spontaneous lifetime Purcell enhancement of 2.08 times. The microwavemeasurement method employing electrical-to-optical conversion, and distinct separation of electrical input and optical output, is more revealing than photoluminescence decay experiments (and the inconvenient overlap of optical input and output).
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42.55.Sa Microcavity and microdisk lasers
42.55.Px Semiconductor lasers; laser diodes

Microwave determination of electron-hole recombination dynamics from spontaneous to stimulated emission in a quantum-well microcavity laser

C. H. Wu, H. W. Then, M. Feng, and N. Holonyak

Appl. Phys. Lett. 96, 131108 (2010); http://dx.doi.org/10.1063/1.3377918 (3 pages) | Cited 3 times

Online Publication Date: 31 March 2010

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By studying the optical microwave frequency response of a microcavity quantum-well vertical cavity surface-emitting laser (VCSEL) in the transition, over a low (a spread-out) mode density, from spontaneous to coherent operation, we resolve the dynamics (spontaneous to stimulated) of electron-hole recombination and reveal the existence of “fast” spontaneous recombination (τBspon<159 ps) in a carrier population generally characterized by a large average lifetime of ∼ 1 ns (Δn/τav = Δn1/τfast+(Δn−Δn1)/τslow,τfast<τslow). The measured average spontaneous lifetime is not a constant but is altered by the device size, geometry, and boundary conditions (e. g., cavity and current input-output boundary conditions).
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72.20.Jv Charge carriers: generation, recombination, lifetime, and trapping
42.55.Px Semiconductor lasers; laser diodes

Photolithographic patterning of subwavelength top emitting colloidal quantum dot based inorganic light emitting diodes on silicon

Ashwini Gopal, Kazunori Hoshino, and Xiaojing Zhang

Appl. Phys. Lett. 96, 131109 (2010); http://dx.doi.org/10.1063/1.3373832 (3 pages) | Cited 2 times

Online Publication Date: 31 March 2010

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The combination of lithographic patterning and nanostamping methods makes it possible to accurately define diffraction-limited multicolor (wavelengths 560–620 nm) light sources on a silicon substrate. We demonstrate a postprocessing technique that utilizes standard photolithography process to pattern the cathode of top emitting diode. Correlation of electroluminescence, photoluminescence, and atomic force microscopy topography showed that the emission region is well defined through the robust multiscale patterning techniques, with the fineness of the emitting area mainly limited by the point spread function of the observing microscope.
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85.60.Jb Light-emitting devices
85.40.Hp Lithography, masks and pattern transfer

975 nm high power diode lasers with high efficiency and narrow vertical far field enabled by low index quantum barriers

P. Crump, A. Pietrzak, F. Bugge, H. Wenzel, G. Erbert, and G. Tränkle

Appl. Phys. Lett. 96, 131110 (2010); http://dx.doi.org/10.1063/1.3378809 (3 pages) | Cited 1 time

Online Publication Date: 31 March 2010

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For optimal coupled power into fiber, high power diode lasers should operate efficiently with smallest possible vertical far field emission angle. Although waveguide and cladding layers can be designed to achieve small angles, the refractive index profile of the active region itself restricts the minimum achievable value. We show that the use of low index quantum barrier layers leads to substantially reduced far field angles, while sustaining high power conversion efficiency. 90 μm stripe lasers that use such designs have narrow vertical far field angles of 30° (95% power content), power conversion efficiency of 58% and operate reliably at 10 W output.
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42.55.Px Semiconductor lasers; laser diodes
42.60.By Design of specific laser systems
42.81.Qb Fiber waveguides, couplers, and arrays

Temporal and spectral control of single-photon frequency upconversion for pulsed radiation

Xiaorong Gu, Kun Huang, Yao Li, Haifeng Pan, E Wu, and Heping Zeng

Appl. Phys. Lett. 96, 131111 (2010); http://dx.doi.org/10.1063/1.3374330 (3 pages) | Cited 7 times

Online Publication Date: 31 March 2010

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We demonstrate efficient single-photon detection at 1.04 μm with quite low background counts by using the frequency upconversion detection technique with pulsed single-photon source and strong pump field prepared from two synchronized fiber lasers. Temporal and spectral control of the pump and signal lasers enabled an upconversion efficiency of 81.1%. As the system was pumped at a wavelength longer than that of the signal, the corresponding background counts were reduced down to 1.5×103 s−1 due to efficient suppression of parametric fluorescence in the periodic poled lithium niobate crystal.
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42.55.Wd Fiber lasers
42.60.By Design of specific laser systems

All-optical switching in an optofluidic polydimethylsiloxane: Liquid crystal grating defined by cast-molding

Luciano De Sio, Julien G. Cuennet, Andreas E. Vasdekis, and Demetri Psaltis

Appl. Phys. Lett. 96, 131112 (2010); http://dx.doi.org/10.1063/1.3377801 (3 pages) | Cited 7 times

Online Publication Date: 1 April 2010

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We report an optofluidic photoswitchable grating, based on a polydimethylsiloxane periodic structure on a glass substrate, separated by a thin liquid crystal film. The polydimethylsiloxane microstructure was realized via high resolution replica molding and was employed to both confine and align a photosensitive nematic liquid crystal. In the absence of any surface treatment, the liquid crystal exhibited homeotropic alignment. By inducing planar alignment on the glass substrate, a hybrid orientation of the liquid crystal was achieved, inducing polarization sensitive transmission. The photosensitivity of the liquid crystal enabled the all-optical control of the grating transmission and 20% diffraction efficiency was measured.
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42.70.Df Liquid crystals
42.79.Dj Gratings
42.70.Jk Polymers and organics

Twinned Fano interferences induced by hybridized plasmons in Au–Ag nanorod heterodimers

Zhong-Jian Yang, Zong-Suo Zhang, Wei Zhang, Zhong-Hua Hao, and Qu-Quan Wang

Appl. Phys. Lett. 96, 131113 (2010); http://dx.doi.org/10.1063/1.3378689 (3 pages) | Cited 15 times

Online Publication Date: 1 April 2010

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We theoretically investigated the plasmon interferences and hybridization in the Au–Ag nanorod heterodimers. Twinned Fanolike profiles are observed in the absorption cross sections of the gold and silver nanorods in the heterodimers, the Fano factors of which have the opposite signs near the antibonding resonances, which are found to be induced by the destructive interferences of two hybridized local surface plasmons. Both the value and sign of the Fano factors could be tuned by adjusting rod-lengths, which could find the applications in the design of plasmonic nanodevices.
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78.66.Bz Metals and metallic alloys
79.60.Bm Clean metal, semiconductor, and insulator surfaces
78.68.+m Optical properties of surfaces
73.20.Mf Collective excitations (including excitons, polarons, plasmons and other charge-density excitations)
73.22.Lp Collective excitations

High-contrast all optical bistable switching in coupled nonlinear photonic crystal microcavities

Shaohui Li and Xuhong Cai

Appl. Phys. Lett. 96, 131114 (2010); http://dx.doi.org/10.1063/1.3378812 (3 pages) | Cited 5 times

Online Publication Date: 1 April 2010

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We present a photonic crystal configuration consisting of a waveguide directly coupled to two microcavities with instantaneous Kerr nonlinearity. We prove that such a configuration can function as a high contrast all optical switch with properly misaligning the resonant frequencies of the constitutional photonic crystal microcavities.
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42.65.Pc Optical bistability, multistability, and switching, including local field effects
42.79.Gn Optical waveguides and couplers
42.65.Jx Beam trapping, self-focusing and defocusing; self-phase modulation
42.70.Qs Photonic bandgap materials

Clustering effects in Ga(AsBi)

Sebastian Imhof, Angela Thränhardt, Alexej Chernikov, Martin Koch, Niko S. Köster, Kolja Kolata, Sangam Chatterjee, Stephan W. Koch, Xianfeng Lu, Shane R. Johnson, Dan A. Beaton, Thomas Tiedje, and Oleg Rubel

Appl. Phys. Lett. 96, 131115 (2010); http://dx.doi.org/10.1063/1.3374884 (3 pages) | Cited 20 times

Online Publication Date: 1 April 2010

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The photoluminescence from a Ga(AsBi) sample is investigated as a function of pump power and lattice temperature. The disorder-related features are analyzed using a Monte Carlo simulation technique. A two-scale approach is introduced to separately account for cluster localization and alloy disorder effects. The corresponding characteristic energy scales of 11 and 45 meV are deduced from the detailed comparison between experiment and simulation.
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78.55.Cr III-V semiconductors
78.66.Fd III-V semiconductors
02.50.Ng Distribution theory and Monte Carlo studies

Phase stabilization of a wave-front dividing four-beam combined amplifier with stimulated Brillouin scattering phase conjugate mirrors

Jae Sung Shin, Sangwoo Park, Hong Jin Kong, and Jin Woo Yoon

Appl. Phys. Lett. 96, 131116 (2010); http://dx.doi.org/10.1063/1.3373629 (3 pages) | Cited 7 times

Online Publication Date: 2 April 2010

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Beam combining method is a promising technique for achieving energy scaling of solid-state lasers. The key technique of the coherent beam combining is the phase control of the stimulated Brillouin scattering wave. In previous works, the amplitude dividing scheme has shown more effective phase control than the wave-front dividing scheme. A recent experiment demonstrated that the phase stabilization in the wave-front dividing scheme can be improved by reducing the beam pointing fluctuation. In this work, a phase stabilization experiment is performed with the wave-front dividing four-beam combined amplifier. The phases are stabilized within λ/25 with an amplified gain of 5.25.
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42.55.Wd Fiber lasers
42.65.Es Stimulated Brillouin and Rayleigh scattering
42.55.Rz Doped-insulator lasers and other solid state lasers
42.79.Bh Lenses, prisms and mirrors
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Gas convection caused by electron pressure drop in the afterglow of a pulsed inductively coupled plasma discharge

G. Cunge, D. Vempaire, and N. Sadeghi

Appl. Phys. Lett. 96, 131501 (2010); http://dx.doi.org/10.1063/1.3368124 (3 pages) | Cited 7 times

Online Publication Date: 29 March 2010

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Neutral depletion is an important phenomenon in high-density plasmas. We show that in pulsed discharges, the neutral depletion caused by the electron pressure Pe plays an important role on radical transport. In the afterglow, Pe drops rapidly by electron cooling. So, a neutral pressure gradient built up between the plasma bulk and the reactor walls, which forces the cold surrounding gas to move rapidly toward the reactor center. Measured drift velocity of Al atoms in the early afterglow of Cl2/Ar discharge by time-resolved laser induced fluorescence is as high as 250 ms−1. This is accompanied by a rapid gas cooling.
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52.80.Hc Glow; corona
52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.25.Fi Transport properties
52.25.Ya Neutrals in plasmas
52.40.Hf Plasma-material interactions; boundary layer effects

Transmission of gigawatt-level microwave using a beam-rotating mode converter in a relativistic backward wave oscillator

H. C. Jung, S. H. Min, G. S. Park, J. An, S. H. Lee, Y. J. Yoon, J. Y. Kim, J. H. Choi, J. H. So, and M. Petelin

Appl. Phys. Lett. 96, 131502 (2010); http://dx.doi.org/10.1063/1.3368692 (3 pages) | Cited 3 times

Online Publication Date: 29 March 2010

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Gigawatt-level circularly polarized radiation was transmitted using a coaxial beam rotating antenna in an X-band relativistic backward wave oscillator. The mode conversion from the TM01 mode to the circularly polarized TE11-like mode was experimentally and numerically shown. The simulated radiation pattern was in good agreement with the measured radiation pattern.
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84.40.Fe Microwave tubes (e.g., klystrons, magnetrons, traveling-wave, backward-wave tubes, etc.)
84.30.Ng Oscillators, pulse generators, and function generators

Pulse shape influence on the atmospheric barrier discharge

T. Martens, A. Bogaerts, and J. van Dijk

Appl. Phys. Lett. 96, 131503 (2010); http://dx.doi.org/10.1063/1.3315881 (3 pages) | Cited 9 times

Online Publication Date: 31 March 2010

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In this letter we compare the effect of a radio-frequency sine, a low frequency sine, a rectangular and a pulsed dc voltage profile on the calculated electron production and power consumption in the dielectric barrier discharge. We also demonstrate using calculated potential distribution profiles of high time and space resolution how the pulsed dc discharge generates a secondary discharge pulse by deactivating the power supply.
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52.80.Pi High-frequency and RF discharges

Plasma treatment of multiwall carbon nanotubes for dispersion improvement in water

Changlun Chen, Akihisa Ogino, Xiangke Wang, and Masaaki Nagatsu

Appl. Phys. Lett. 96, 131504 (2010); http://dx.doi.org/10.1063/1.3377007 (3 pages) | Cited 22 times

Online Publication Date: 31 March 2010

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Microwave excited Ar/H2O surface-wave plasma was used to treat multiwall carbon nanotubes (MWCNTs) to modify their surface characteristics and thus improve their dispersion capability in water. Changes in the atom composition and structure properties of MWCNTs were analyzed using x-ray photoelectron spectroscopy and Raman spectroscopy, and the surface morphology of MWCNTs was observed by field emission scanning electron microscopy and scanning transmission electron microscopy. The results indicated that Ar/H2O plasma treatment greatly enhanced the content of oxygen, and modified surface microstructure properties. The integrity of nanotube patterns, however, was not damaged.
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81.07.De Nanotubes
52.77.-j Plasma applications
81.65.-b Surface treatments
82.80.Pv Electron spectroscopy (X-ray photoelectron (XPS), Auger electron spectroscopy (AES), etc.)
78.67.Ch Nanotubes
78.30.Na Fullerenes and related materials

Characteristics of extreme ultraviolet emission from a discharge-produced potassium plasma for surface morphology application

Takeshi Higashiguchi, Hiromitsu Terauchi, Noboru Yugami, Toyohiko Yatagai, Wataru Sasaki, Rebekah D’Arcy, Padraig Dunne, and Gerry O’Sullivan

Appl. Phys. Lett. 96, 131505 (2010); http://dx.doi.org/10.1063/1.3368705 (3 pages) | Cited 5 times

Online Publication Date: 1 April 2010

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We have demonstrated a discharge-produced microplasma extreme ultraviolet source based on a pure potassium vapor. Potassium ions produced strong broadband emission around 40 nm with a bandwidth of 8 nm (full width at half-maximum). The current-voltage characteristics of microdischarge suggest that the source operates in a hollow cathode mode. By comparison with atomic structure calculations, the broadband emission is found to be primarily due to 3d−3p transitions in potassium ions ranging from K2+ to K4+.
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52.50.Jm Plasma production and heating by laser beams (laser-foil, laser-cluster, etc.)
52.80.Hc Glow; corona
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An ab initio investigation of boron nanotube in ringlike cluster form

Fu-Yang Tian, Yuan-Xu Wang, V. C. Lo, and Jiang Sheng

Appl. Phys. Lett. 96, 131901 (2010); http://dx.doi.org/10.1063/1.3377790 (3 pages)

Online Publication Date: 31 March 2010

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Four types of boron nanotubes (BNTs) in the form of double-ring basic units are theoretically predicted. The structure, stability, and electronic properties of these stable BNTs are investigated by the first-principles calculations. The BNT formed by the basic unit with one hole every six atoms on each ring is found to be more stable than those with other three types of basic units. By increasing diameter for boron ring, the stability is enhanced. The density of state demonstrates that BNTs formed by these basic units are metallic.
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61.46.Fg Nanotubes
73.22.-f Electronic structure of nanoscale materials and related systems
71.15.-m Methods of electronic structure calculations

Electrically surface-driven switchable wettability of liquid crystal/polymer composite film

Ya-Ping Chiu, Cheng-Yu Shen, Wen-Ching Wang, Ting-Yu Chu, and Yi-Hsin Lin

Appl. Phys. Lett. 96, 131902 (2010); http://dx.doi.org/10.1063/1.3378688 (3 pages) | Cited 3 times

Online Publication Date: 31 March 2010

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This study demonstrates the electrical control of the surface wettability of liquid crystal and polymer composite film. The application of external voltages significantly affects the surface wettability of the film. This study uses atomic force microscopy to quantitatively characterize the fundamental mechanism responsible for the structurally driven changes in surface properties at various applied voltages. The surface wettability transitions of the film are electrically driven, as shown by reorganized liquid crystal molecules. Measurements of the voltage-dependent surface wettability of the composite film suggest approaches to supporting control applications of future electro-optical nanotechnology devices.
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68.08.Bc Wetting
68.37.Ps Atomic force microscopy (AFM)
68.35.B- Structure of clean surfaces (and surface reconstruction)
68.55.am Polymers and organics
61.30.-v Liquid crystals
61.30.Hn Surface phenomena: alignment, anchoring, anchoring transitions, surface-induced layering, surface-induced ordering, wetting, prewetting transitions, and wetting transitions

Twin microstructure dependent mechanical response in Ni–Mn–Ga single crystals

Ladislav Straka, Natalyia Lanska, Kari Ullakko, and Alexei Sozinov

Appl. Phys. Lett. 96, 131903 (2010); http://dx.doi.org/10.1063/1.3373608 (3 pages) | Cited 30 times

Online Publication Date: 1 April 2010

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Ni–Mn–Ga single crystals with a twinning stress of about 0.1 MPa were studied. They showed a tendency to stay in a single variant state and to retain only one or very few twin boundaries during martensite reorientation induced by an external stress or magnetic field. This makes the crystals problematic for application in a magnetic actuator. To solve the issue, we introduced many parallel twin boundaries into the crystals by bending. However, this twin microstructure was not stable under cycling load. Additionally, it exhibited a twinning stress of 0.8 MPa—about ten times higher than a crystal with a single boundary.
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61.72.Mm Grain and twin boundaries
81.40.Lm Deformation, plasticity, and creep
62.20.F- Deformation and plasticity

Microstructural evolution of Mn-rich antiferromagnetic Mn–Cu alloy under temperature field

J. Man, J. H. Zhang, and Y. H. Rong

Appl. Phys. Lett. 96, 131904 (2010); http://dx.doi.org/10.1063/1.3378810 (3 pages) | Cited 2 times

Online Publication Date: 1 April 2010

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This paper reports the microstructural evolution during forward and reverse martensitic transformations as temperature changes in Mn-rich Mn–Cu alloy. The driving force of martensitic transformation and transformation strain in time-dependent Ginzburg–Laudau kinetic equation is considered as functions of temperature. The computer simulation by using a three-dimensional phase-field theory shows that fct (011) twin martensites grow up with decreasing temperature and shrink with increasing temperature under martensitic transformation temperature, Ms. The forward and reverse processes are entirely reversible and show a very small hysteresis. It is proved that the relaxation of stored strain energy during the forward martensitic transformation plays a key role when reverse martensitic transformation takes place. The simulated results are consistent with experiments.
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81.30.Kf Martensitic transformations
81.30.Hd Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder
75.50.Ee Antiferromagnetics
64.70.K- Solid-solid transitions
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