Bandwidth of Lightwave-Driven Electronic Response from Metallic Nanoantennas

Area of Science:

• Ultrafast optics and electron dynamics.
• Nano-optics and plasmonics.
• Quantum tunneling phenomena.

Background:

• Lightwave electronics enable precise control at high optical frequencies.
• Previous work demonstrated time-domain analysis of optical waveforms via lightwave-driven electron emission.
• The influence of gate waveform on measurement transfer functions was not understood.

Purpose of the Study:

• To investigate the effect of the gate waveform on the measurement transfer function in lightwave electronics.
• To experimentally determine bandwidth limitations in lightwave-driven electron emission.
• To validate theoretical models for lightwave electronic response.

Main Methods:

• Generating electrons using a 10-cycle pulse in the optical tunneling regime.
• Perturbing the electron emission response with a 1.5-cycle pulse.
• Comparing experimental measurements with time-dependent Schrödinger equation (TDSE) simulations and analytical models.

Main Results:

• Experimental measurement of bandwidth limitations imposed by the electron emission process.
• Revelation of temporal properties of the electronic response.
• Confirmation of the Fowler-Nordheim model's accuracy for lightwave electronic response from noble metals.

Conclusions:

• The study elucidates the impact of electronic response temporal properties on the small-signal transfer function.
• Experimental results validate the Fowler-Nordheim model for noble metal nanoantennas.
• Proposed extension of techniques for sub-cycle electronic response characterization using harmonic frequency mixing.