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1. Temperature-induced antiferromagnetic interlayer exchange coupling in (Ga,Mn)(As,P)-based trilayer structure

   https://doi.org/10.1063/5.0009252  

   Chongthanaphisut, Phunvira; Lee, Kyung Jae; Park, Seongjin; Jang, Jiyoung; Lee, Sanghoon; Liu, X.; Dobrowolska, M.; Furdyna, J. K. (May 2020, Journal of Applied Physics)
2. Spin–orbit torque switching in a single (Ga,Mn)(As,P) layer with perpendicular magnetic anisotropy

   https://doi.org/10.1063/5.0064236  

   Park, Seongjin; Lee, Kyung_Jae; Lee, Sanghoon; Liu, Xinyu; Dobrowolska, Margaret; Furdyna, Jacek_K (October 2021, APL Materials)

   We report the observation of current induced spin–orbit torque (SOT) switching of magnetization in a (Ga,Mn)(As,P) film using perpendicular magnetic anisotropy. Complete SOT switching of magnetization was achieved with current densities as low as 7.4 × 105 A/cm2, which is one to two orders of magnitude smaller than that normally used for SOT switching in ferromagnet/heavy metal bilayer systems. The observed magnetization switching chirality during current scans is consistent with SOT arising from spin polarization caused by the Dresselhaus-type spin–orbit-induced (SOI) fields. The magnitudes of effective SOI fields corresponding to the SOT were obtained from shifts of switching angles in angular dependent Hall measurements observed for opposite current polarities. By measuring effective SOI fields for the [11̄0] and the [110] current directions, we were then able to separate the values of the Dresselhaus-type (HeffD) and Rashba (HeffR) SOI fields. At a current density of 6.0 × 105 A/cm2, these values are HeffD=6.73Oe and HeffR=1.31Oe, respectively. The observed ratio of about 5:1 between Dresselhaus-type and Rashba SOI fields is similar to that observed in a GaMnAs film with an in-plane magnetic anisotropy. 

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3. Measured limits on amplitude dependence of mechanical loss in substrate-transferred $\mathrm{Ga}\mathrm{As}/{\mathrm{Al}}_{0.92}{\mathrm{Ga}}_{0.08}\mathrm{As}$ coatings

   https://doi.org/10.1103/PhysRevD.106.042001  

   Gretarsson, Elizabeth M.; Gretarsson, Andri M.; Cole, Garrett D.; Harry, Gregory M.; Kinley-Hanlon, Maya M.; Jones, R. Jason; Penn, Steven D. (August 2022, Physical Review D)

   AIP (Ed.)

   In this Perspective, we summarize the status of technological development for large-area and low-noise substrate-transferred GaAs/AlGaAs (AlGaAs) crystalline coatings for interferometric gravitational-wave (GW) detectors. These topics were originally presented as part of an AlGaAs Workshop held at American University, Washington, DC, from 15 August to 17 August 2022, bringing together members of the GW community from the laser interferometer gravitational-wave observatory (LIGO), Virgo, and KAGRA collaborations, along with scientists from the precision optical metrology community, and industry partners with extensive expertise in the manufacturing of said coatings. AlGaAs-based crystalline coatings present the possibility of GW observatories having significantly greater range than current systems employing ion-beam sputtered mirrors. Given the low thermal noise of AlGaAs at room temperature, GW detectors could realize these significant sensitivity gains while potentially avoiding cryogenic operation. However, the development of large-area AlGaAs coatings presents unique challenges. Herein, we describe recent research and development efforts relevant to crystalline coatings, covering characterization efforts on novel noise processes as well as optical metrology on large-area (∼10 cm diameter) mirrors. We further explore options to expand the maximum coating diameter to 20 cm and beyond, forging a path to produce low-noise mirrors amenable to future GW detector upgrades, while noting the unique requirements and prospective experimental testbeds for these semiconductor-based coatings. 

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4. Ternary Diagrams of Ni-Mn-Ga from First Principles

   https://doi.org/10.4028/www.scientific.net/MSF.845.130  

   Sokolovskiy, Vladimir V.; Sokolovskaya, Yuliya A.; Zagrebin, Mikhail A.; Buchelnikov, Vasiliy D.; Zayak, Alexey T. (March 2016, Materials Science Forum)

   The composition dependences of the magnetic and elastic properties of Ni-Mn-Ga Heusleralloys are investigated by using ab initio calculations. The off-stoichiometric compositions are real-ized by the coherent-potential approximation. Two types of off-stoichiometric approaches are pro-posed. Through a series of researches, the equilibrium lattice constants, bulk modulus, magnetic mo-ments, formation energies of Ni-Mn-Ga alloys are obtained and mapped onto ternary diagrams. 

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5. Magnetic domain-twin boundary interactions in Ni–Mn–Ga

   https://doi.org/10.1016/j.actamat.2020.03.045  

   Veligatla, Medha; Garcia-Cervera, Carlos J.; Müllner, Peter (July 2020, Acta Materialia)