Highly efficient THz four-wave mixing in doped silicon

Nils Dessmann; Nguyen H Le; Viktoria Eless; Steven Chick; Kamyar Saeedi; Alberto Perez-Delgado; Sergey G Pavlov; Alexander F G van der Meer; Konstantin L Litvinenko; Ian Galbraith; Nikolay V Abrosimov; Helge Riemann; Carl R Pidgeon; Gabriel Aeppli; Britta Redlich; Benedict N Murdin

doi:10.1038/s41377-021-00509-6

Highly efficient THz four-wave mixing in doped silicon

Light Sci Appl. 2021 Apr 1;10(1):71. doi: 10.1038/s41377-021-00509-6.

Authors

Nils Dessmann¹, Nguyen H Le², Viktoria Eless³, Steven Chick⁴, Kamyar Saeedi³, Alberto Perez-Delgado⁴, Sergey G Pavlov⁵, Alexander F G van der Meer³, Konstantin L Litvinenko⁴, Ian Galbraith⁶, Nikolay V Abrosimov⁷, Helge Riemann⁷, Carl R Pidgeon⁶, Gabriel Aeppli^{8

9

10}, Britta Redlich³, Benedict N Murdin⁴

Affiliations

¹ Radboud University, Institute for Molecules and Materials, HFML-FELIX, Nijmegen, The Netherlands. nils.dessmann@ru.nl.
² Advanced Technology Institute and Department of Physics, University of Surrey, Guildford, GU2 7XH, UK. h.le@surrey.ac.uk.
³ Radboud University, Institute for Molecules and Materials, HFML-FELIX, Nijmegen, The Netherlands.
⁴ Advanced Technology Institute and Department of Physics, University of Surrey, Guildford, GU2 7XH, UK.
⁵ Institute of Optical Sensor Systems, German Aerospace Center, Berlin, Germany.
⁶ Institute of Photonics and Quantum Sciences, SUPA, Heriot-Watt University, Edinburgh, UK.
⁷ Leibniz-Institut für Kristallzüchtung (IKZ), Berlin, Germany.
⁸ Laboratory for Solid State Physics, ETH Zürich, 8093, Zürich, Switzerland.
⁹ Institut de Physique, EPFL, 1015, Lausanne, Switzerland.
¹⁰ Paul Scherrer Institute, 5232, Villigen, Switzerland.

Abstract

Third-order non-linearities are important because they allow control over light pulses in ubiquitous high-quality centro-symmetric materials like silicon and silica. Degenerate four-wave mixing provides a direct measure of the third-order non-linear sheet susceptibility χ⁽³⁾L (where L represents the material thickness) as well as technological possibilities such as optically gated detection and emission of photons. Using picosecond pulses from a free electron laser, we show that silicon doped with P or Bi has a value of χ⁽³⁾L in the THz domain that is higher than that reported for any other material in any wavelength band. The immediate implication of our results is the efficient generation of intense coherent THz light via upconversion (also a χ⁽³⁾ process), and they open the door to exploitation of non-degenerate mixing and optical nonlinearities beyond the perturbative regime.