Atomically thin heterostructure with gap-mode plasmon for overcoming trade-off between photoresponsivity and response time

• 作者: Khang June Lee Cheolmin Park Hyeok Jun Jin Gwang Hyuk Shin Sung-Yool Choi
• 来源期刊: 纳米研究（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: Research Articles
• 页码范围: 1305-1310
• 页数: 6页
• 语种: 英文

摘要

Two-dimensional (2D) materials have recently provided a new perspective on optoelectronics because of their unique layered structure and excellent physical properties.However,their potential use as optoelectric devices has been limited by the trade-off between photoresponsivity and response time.Here,based on a vertically stacked atomically thin p-n junction,we propose a gap-mode plasmon structure that simultaneously enables enhanced responsivity and rapid photodetection.The atomically thin 2D materials act as a spacer for enhancing the gap-mode plasmons,and their short transit length in the vertical direction allows fast photocarrier transport.We demonstrate a high responsivity of up to 8.67 A/W with a high operation speed that exceeds 35 MHz under a 30 nW laser power.Spectral photocurrent,absorption,and a numerical simulation are used to verify the effectiveness of the gap-mode plasmons in the device.We believe that the design strategy proposed in this study can pave the way for a platform to overcome the trade-off between responsivity and response time.