Non-radiative relaxation and rectification behavior of metal/semiconductor tetrapod heterostructures

作者：Haldar Krishna Kanta; Kundu Simanta; Patra Amitava^*

来源：Applied Physics Letters, 2014, 104(6): 063110.

DOI：10.1063/1.4865398

The metal-semiconductor hetero-structures have recently emerged as functional materials for their potential applications in the areas of photonic, optoelectronic, and other fields. Here, we discuss the structural characterization of Au/CdSe tetrapod hetero-structures by using high-resolution transmission electron microscope, high angle annular dark field-scanning transmission electron microscopic, and X-ray diffraction. The blue shifting of the plasmonic band and red shifting of the excitonic band suggest a strong surface plasmon-exciton interaction between Au and CdSe in Au/CdSe tetrapod heterostructure. A significant photoluminescence quenching (83.4%) of CdSe nanorod (NR) is observed in the presence of Au nanoparticle in Au/CdSe tetrapod heterostructure. The radiative and nonradiative decay rates of CdSe nanorods are found to be modified in Au/CdSe tetrapod structures and the nonradiative rate changes from 1.91 x 10(7) s(-1) to 9.33 x 10(9) s(-1) for CdSe NR to Au/CdSe tetrapod structure, respectively. Current-voltage characteristics of Au/CdSe heterostructure exhibit the rectification property with a threshold voltage of about 0.85V and the rectifying ratio is 140 which can open up avenues for developing challenging devices.

• 出版日期2014-2-10