论文标题
Brillouin Light Scractroscopicy的不增压BI2SR2CACU2O（8+Delta）晶体中的长波长声子动力学
Long-wavelength phonon dynamics in incommensurate Bi2Sr2CaCu2O(8+delta) crystals by Brillouin light scattering spectroscopy
论文作者
论文摘要
使用Brillouin光散射光谱探测了高-TC超导体BI2SR2CACU2O（8+Delta）晶体中的室温声子动力学。观察并确定了八种不同的声学模式，包括两种准纵向散装模式和四种准透明散装模式。在光谱中还观察到了〜95 GHz的频率移动峰值，而行为也观察到了光学声音。这些模式的存在和性质是BI2SR2CACU2O（8+delta）的不均匀结构的表现，并表明它可以归类为由两个弱相互作用的sublattices组成的所谓的复合不相关的晶体。从两个测得的准纵向声速度获得的M1/M2 = 0.36的质量比导致BI2SR2O4和CACU2O4的sublattice分配。 Brillouin数据还将上限〜10 GHz置于相应和不相当的声子动力学之间的交叉频率上。
Room temperature phonon dynamics in crystals of the high-Tc superconductor Bi2Sr2CaCu2O(8+delta) were probed using Brillouin light scattering spectroscopy. Eight distinct acoustic modes were observed and identified, including two quasi-longitudinal bulk modes and four quasi-transverse bulk modes. A peak at a frequency shift of ~95 GHz with behaviour reminiscent of an optic phonon was also observed in the spectra. The existence and nature of these modes is a manifestation of the incommensurate structure of Bi2Sr2CaCu2O(8+delta) and suggests that it may be categorized as a so-called composite incommensurate crystal comprised of two weakly interacting sublattices. A mass ratio of m1/m2=0.36 obtained from the two measured quasi-longitudinal acoustic velocities led to sublattice assignments of Bi2Sr2O4 and CaCu2O4. The Brillouin data also places an upper limit of ~10 GHz on the crossover frequency between commensurate and incommensurate phonon dynamics.
