Periodically pulsed laser-assisted tunneling may generate terahertz radiation

Hagmann, Mark J.; Coombs, David G.; Yarotski, Dmitry Anatolievitch

doi:10.1116/1.4979549

Periodically pulsed laser-assisted tunneling may generate terahertz radiation

Journal Article · Mon Apr 24 00:00:00 EDT 2017 · Journal of Vacuum Science and Technology B

DOI:https://doi.org/10.1116/1.4979549· OSTI ID:1505991

Hagmann, Mark J. ^[1]; Coombs, David G. ^[1]; ^[2]

NewPath Research L.L.C., Salt Lake City, UT (United States)
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

In this work, a mode-locked ultrafast laser focused on the tunneling junction of a scanning tunneling microscope superimposes harmonics of the laser pulse repetition frequency on the direct current tunneling current. The power measured at the first 200 harmonics (up to 14.85 GHz) varies as the inverse square of the frequency due to shunting by the stray capacitance and the resistance in the circuit. However, Fourier analysis suggests that within the tunneling junction there is no significant decay of the harmonics until terahertz frequencies comparable to the reciprocal of the laser pulse-width. Two different types of analysis are used to model the generation of the frequency comb within the tunneling junction. Similar results are obtained, suggesting that the harmonics may extend to terahertz frequencies. Thus, the tunneling junction may be used as a subnanometer sized source of terahertz radiation.

Research Organization:: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Organization:: USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)

Grant/Contract Number:: 89233218CNA000001; AC52-06NA25396

OSTI ID:: 1505991

Alternate ID(s):: OSTI ID: 1680015

Report Number(s):: LA-UR--17-20587; LA-UR-16-28593

Journal Information:: Journal of Vacuum Science and Technology B, Journal Name: Journal of Vacuum Science and Technology B Journal Issue: 3 Vol. 35; ISSN 2166-2746

Publisher:: American Vacuum Society/AIPCopyright Statement

Country of Publication:: United States

Language:: English

Cited By (2)

Scanning frequency comb microscopy—A new method in scanning probe microscopy Hagmann, M. J. AIP Advances, Vol. 8, Issue 12 https://doi.org/10.1063/1.5047440	journal	December 2018
Simulation of sub-nm carrier profiling by scanning frequency comb microscopy Hagmann, M. J.; Wiedemeier, J. AIP Advances, Vol. 9, Issue 5 https://doi.org/10.1063/1.5092282	journal	May 2019