具有分离门电抽运石墨烯中电子-空穴等离子体的冷却效应  

Effect of cooling of electron-hole plasma in electrically pumped graphene layer structures with split gates

作　　者：张玉萍[1] 刘陵玉[1] 陈琦[2] 冯志红[3] 王俊龙[3] 张晓[1] 张洪艳[1] 张会云[1] 

机构地区：[1]山东科技大学理学院青岛市太赫兹技术重点实验室,青岛266510 [2]中国工程物理研究院电子工程研究所,绵阳621900 [3]专用集成电路重点实验室,石家庄050051

出　　处：《物理学报》2013年第9期377-383,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61001018);山东省自然科学基金(批准号:ZR2011FM009,ZR2012FM011);山东科技大学杰出青年科学基金(批准号:2010KYJQ103);山东省高等学校科技计划项目(批准号:J11LG20);青岛市科技计划项目(批准号:11-2-4-4-(8)-jch,10-3-4-2-1-jch);山东科技大学科技创新基金(批准号:YCA120378)资助的课题~~

摘　　要：本文研究了室温条件下具有分离门的电诱导石墨烯n-i-p结构中,与电子和空穴注入有关的粒子数反转效应.考虑n区横向电场的屏栅效应,计算了电子-空穴的有效温度与门电压以及光声子的有效温度与门电压的关系,结果表明注入可以导致n区中电子-空穴等离子体显著冷却,直至低于晶格温度;计算了电流-电压特性以及与频率有关的动态电导率,在一定的电压下,动态电导率在太赫兹频段可以为负值.研究表明电子-空穴等离子体冷却能够加强负动态电导率效应,提高实现太赫兹激射的可行性.We have studied the effect of population inversion associated with the electron and hole injection in graphene layer n-i-p structures with split gates at room temperature. Considering the transverse electric field screening of the n-section, we calculated the dependence of the electron-hole effective temperature and optical phonon effective temperature on the gate-voltage. It is shown that the injection can lead to cooling of the electron-hole plasma in n-section to the temperatures lower than the lattice temperature. The current-voltage characteristics, and the frequency-dependent dynamic conductivity are calculated, the frequency-dependent dynamic conductivity can be negative in the terahertz frequency range at a certain applied voltage. The study demonstrates that electron-hole plasma cooling can enhance the negative dynamic conductivity effect and improve the feasibility of terahertz lasing.

关 键 词：石墨烯 n-i-p结构 有效温度 动态电导率 

分 类 号：O53[理学—等离子体物理]