Strain-induced spatially indirect exciton recombination in zinc-blende/wurtzite CdS heterostructures  

作　　者：Dehui Li Yang Liu Maria de la Mata Cesar Magen Jordi Arbiol Yuanping Feng Qihua Xiong 

机构地区：[1]Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore [2]Institut de Ciencia de Materials de Barcelona, ICMAB-CSIC, Campus de la UAB, 08193 Bellaterra, Catalonia, Spain [3]Laboratofio de Microscopias Avanzadas (LMA), Instituto de Nanociencia de Aragon (INA) ARAID and Departamento de Fisica de la Materia Condensada, Universidad de Zaragoza, 50018 Zaragoza, Spain [4]Institucio Catalana de Recerca i Estudis Avancats (ICREA), 08010 Barcelona, Catalonia, Spain [5]Institut Catala de Nanociencia i Nanotecnologia (ICN2), Campus UAB, 08193 Bellaterra, Catalonia, Spain [6]Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore [7]Division of Microelectronics, School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore 639798,Singapore

出　　处：《Nano Research》2015年第9期3035-3044,共10页纳米研究（英文版）

摘　　要：Strain engineering provides an effective mean of tuning the fundamental properties of semiconductors for electric and optoelectronic applications. Here we report on how the applied strain changes the emission properties of hetero- structures consisting of different crystalline phases in the same CdS nanobelts. The strained portion was found to produce an additional emission peak on the low-energy side that was blueshifted with increasing strain. Furthermore, the additional emission peak obeyed the Varshni equation with temperature and exhibited the band-filling effect at high excitation power. This new emission peak may be attributed to spatially indirect exciton recombination between different crystalline phases of CdS. First-principles calculations were performed based on the spatially indirect exciton recombination, and the calculated and experimental results agreed with one another. Strain proved to be capable of enhancing the anti-Stokes emission, suggesting that the efficiency of laser cooling may be improved by strain engineering.

关 键 词：strain CdS nanobelts photoluminescence spatially indirect excitonrecombination inter-crystalline PHASETRANSITION 

分 类 号：O[理学]