We report on the precise determination of both the band gap E$_\text{g}$, and the characteristic energy $U$ of the band tail of localized defect states, for monocrystalline Ag$_2$ZnSnSe$_4$. Both photoluminescence excitation and time-resolved photoluminescence studies lead to E$_\text{g} = 1223\pm3$ meV, and $U = 20\pm3$ meV, at 6 K. The interest of the methodology developed here is to account quantitatively for the time-resolved photoluminescence and photoluminescence excitation spectra by only considering standard textbook density of states, and state filling effects. Such an approach is different from the one most often used to evaluate the energy extent of the localized states, namely by measuring the energy shift between the photoluminescence emission and the excitation one -- the so-called Stokes shift. The advantage of the present method is that no arbitrary choice of the low power excitation has to be done to select the photoluminescence emission spectrum and its peak energy.
Temperature and crystallographic orientation dependence of the anisotropic magnetoresistance in epitaxial Fe65Co35 thin films
Universidad Nacional de Ingeniería（国立工程学院）；Universidad Católica San Pablo（圣保罗天主教大学）；Instituto Balseiro, Universidad Nacional de Cuyo, Comisión Nacional de Energía Atómica（巴尔塞罗研究所，门多萨国立大学，国家原子能委员会）；Instituto de Nanociencia y Nanotecnología (CNEA - CONICET)（纳米科学与技术研究所（国家原子能委员会-国家科学研究和技术委员会））；Comisión Nacional de Energía Atómica（国家原子能委员会）
Route to in situ synthesis of epitaxial Pr2Ir2O7 thin films guided by thermodynamic calculations
原位生长烧绿石铱酸盐薄膜一直是一个长期存在的挑战，这是由于Ir在低温下的低反应性以及诸如IrO 3（g）和IrO 2（g）的挥发性气体物质在高温和高氧分压下的蒸发。为了解决这一挑战，我们结合热力学分析的Pr-Ir-O2系统的实验结果从传统的物理气相沉积（PVD）技术的共溅射。我们的研究结果表明，只有高的生长温度产生足够的结晶度利用和定制所需的拓扑电子性能的薄膜。热力学计算表明，需要高沉积温度和气体种类O2（g）和IrO 3（g）的高分压来稳定Pr 2 Ir 2 O 7。我们进一步发现，气体种类的分压要求是超出了可实现的任何传统的PVD技术。我们的实验表明，传统的PVD生长参数只产生Pr 3 IrO 7，这一结论，我们再现与理论计算。我们的研究结果提供了坚实的证据表明，在原位合成的Pr 2 Ir 2 O 7薄膜的束缚不能生长与氧分压的顺序为10托，固有的PVD工艺的限制。因此，我们建议高压技术，特别是化学气相沉积（CVD），作为合成Pr 2 Ir 2 O 7的途径，因为这可以支持原位稳定Pr 2 Ir 2 O 7所需的高压下的薄膜沉积。
Single-crystal epitaxial europium iron garnet films with strain-induced perpendicular magnetic anisotropy: structural, strain, magnetic, and spin transport properties
