【摘要】 利用光学办法在固体中产生和检测频率为10¹²Hz的特超声声子,以及研究这些特超声声子在固体中的行为,是近几年发展起来的新领域,对于超声物理和固体物理研究是很有意义的。本文前三部分介绍了在压电晶体中利用远红外脉冲激光的表面激发产生特超声声子,以及利用激光激发磁性离子的晶场劈裂能级,引起声子感应跃迁,产生很强的声发射。在某些情况下,可以实现受激发射。在第四部分中介绍了处于激发态的磁性离子通过声子感应吸收跃迁,可以感应出附加的荧光辐射,借助这种感应荧光可以实现特超声的相干检测。最后简要介绍了特超声声子在固体物理研究中的应用。更多还原

【Abstract】 Generation and detection of hypersonic phonons with frequencyup to 1012 Hz by optical technique, and investigation of their behaviorin solid state, are a new field developed recently. which is attractiveto research workers in ultrasonics and solid state physics. In the firstthree parts of the present article, the principle to generate hypersonicphonons by surface excitation on a piezoelectric crystal using a farinfrared pulse laser is introduced, strong phonon emission, andstimulated phonon emission in some cases, through phonon-inducedradiation transition between crystal field splitting levels of magneticimpurities excited by lasers, are described. In the fourth part it iselucidated that coherent detection of hypersonic phonons can be realizedby means of measuring an additional fluorescent emission induced byphonon absorption transition at excited magnetic ions. Finally a briefintroduction of applications of hypersonic phonons to solid statephysics is given.更多还原