Year: 2024
Type: article
Abstract: Nanoscale material systems are central to next-generation optoelectronic and quantum technologies, yet their development remains hindered by limited characterization tools, particularly at terahertz (THz) frequencies. Far-field THz spectroscopy techniques lack the sensitivity for investigating individual nanoscale systems, whereas in near-field THz nanoscopy, surface states, disorder, and sample-tip interactions often mask the response of the entire nanoscale system. Here, we present a THz resonance-amplified near-field spectroscopy technique that can detect subtle conductivity changes in isolated nanoscale systems─such as a single InAs nanowire─under ultrafast photoexcitation. By exploiting the spatial localization and resonant field enhancement in the gap of a bowtie antenna, our approach enables precise measurements of the nanostructures through shifts in the antenna resonant frequency, offering a direct means of extracting the system response, and unlocking investigations of ultrafast charge-carrier dynamics in isolated nanoscale and microscale systems.
Source: Nano Letters
Institutions: University College London, University of Cambridge, University of Oxford, ETH Zurich, Institute for Quantum Electronics, Australian National University, Australian Research Council, ARC Centre of Excellence for Transformative Meta-Optical Systems, The University of Adelaide, University of Birmingham
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
Awards: G1605311361, Unveiling electron motion at surfaces and interfaces on ultrashort length and ultrafast time scales, EPSRC Centre for Doctoral Training in Integrated Functional Nano (i4Nano), G3204812816, Ultrafast Terahertz Polarimetry Enabled by Semiconductor Nanowire Sensors, G4413893389, G6265852920, EPSRC Centre for Doctoral Training in Connected Electronic and Photonic Systems (CEPS), Terahertz frequency devices and systems for ultrahigh capacity wireless communications, ARC Centre of Excellence for Transformative Meta-Optical Systems, DTP 2020-2021 University College London
OpenAlex ID: W4404722726