Terahertz Emitters by TeraSpinTec

I. What is a Terahertz Emitter? Which one to choose?

Principle of a terahertz emitter driven by femtosecond laser excitation

A terahertz emitter can generate terahertz radiation upon optical excitation. For generating short terahertz pulses, typically ultrafast laser excitation is used. Here, a femtosecond laser pulse triggers subpicosecond charge dynamics inside the terahertz emitter leading to the emission of a terahertz pulse. Depending on the material of the terahertz emitter, the terahertz pulse can strongly differ in their spectrum, amplitude and polarization. 

There are two main classes of terahertz emitters depending on the pulse energy of the laser excitation:

1. Terahertz emitters operated with low excitation pulse energies (<nJ to μJ)

      • This class of terahertz emitters is used for linear terahertz spectroscopy. Typical candidates include photoconductive antennas (1 to 3 THz), nonlinear optical crystals (1 to 8 THz) and spintronic terahertz emitters (1 to >30 THz).
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Comparison of time domain terahertz waveforms from different terahertz emitter types

2. Terahertz emitters operated with high excitation pulse energies (μJ to >mJ)

      • These terahertz emitters can generate extremely high terahertz electric field strengths in the range of MV/cm. Examples include lithium niobate (1 to 2 THz), organic crystal (1 to 8 THz, pronounced spectral gaps), plasma sources (1 to >20 THz, typically more unstable) and large-scale spintronic terahertz emitters (1 to >20 THz).
Direct comparison of a lithium niobate and a large-scale spintronic terahertz emitter (T-Spin2X) using 5 mJ excitation

II. TeraSpinTec’s Spintronic THz Technology

Schematic of a spintronic terahertz emitter

Our spintronic terahertz emitters utilize thin-film heterostructures that convert femtosecond laser pulses into THz radiation via spin–orbit coupling.

Key features include:

    • Broadband THz emission (0.1–30 THz)

    • High optical-to-THz conversion efficiency

    • Compact, alignment-free design

    • Stable operation and long lifetime

This makes TeraSpinTec’s emitters ideal for spectroscopy, ultrafast dynamics studies, and THz imaging. 

Terahertz Spectrum from a Spintronic Terahertz Emitter

Depending on your pump-pulse duration, our spintronic terahertz emitter can generate ultrabroadband terahertz pulses with varying bandwidth. Below, you can find some exemplary spectra that might serve as an estimate for the achievable terahertz bandwith. The presented spectra refer to the terahertz electric field in the detection focus, that is, after refocussing the emitted terahertz beam. For the corresponding propagation function from the spintronic terahertz emitter to the detection focus position, a typical function linear in frequency is assumed. The respective pulse duration refers to the full width at half maximum of a pump pulse with a Gaussian intensity profile. 

  • 10 fs
  • 20 fs
  • 30 fs
  • 40 fs
  • 50 fs
  • 60 fs
  • 80 fs
  • 100 fs
  • 120 fs
  • 160 fs
  • 200 fs