Massachusetts Institute of Technology

Lawrence Livermore National Security, LLC

Evan J Reed

Marin Soljacic

John Dimitris Joannopoulos

Steven G Johnson

Mihai Ibanescu

Aristeidis Karalis

Yoel Fink

Elefterios Lidorikis

Peter Thomas Rakich

Erich P Ippen

Maksim Skorobogatiy

Rafif E Hamam

Michael Robert Armstrong

David Chan

Kerwyn C Huang

Maksim Skorobagatiy

Strain waves of THz frequencies can coherently generate radiation when they propagate past an interface between materials with different piezoelectric coefficients. Such radiation is of detectable amplitude and contains sufficient information to determine the time-dependence of the strain wave with unprecedented subpicosecond, nearly atomic time and space resolution.

Method for generation of THz frequency radiation and sensing of large amplitude material strain waves in piezoelectric materials

A system and a method for generating terahertz (THz) radiation are provided. The system includes a photonic crystal structure comprising at least one nonlinear material that enables optical rectification. The photonic crystal structure is configured to have the suitable transverse dispersion relations and enhanced density photonic states so as to allow THz radiation to be emitted efficiently when an optical or near infrared pulse travels through the nonlinear part of the photonic crystal.

Efficient terahertz sources by optical rectification in photonic crystals and metamaterials exploiting tailored transverse dispersion relations

A new class of surface plasmon waveguides is presented. The basis of these structures is the presence of surface plasmon modes, supported on the interfaces between the dielectric regions and the flat unpatterned surface of a bulk metallic substrate. The waveguides discussed here are promising to have significant applications in the field of nanophotonics by being able to simultaneously shrink length, time and energy scales, allowing for easy coupling over their entire bandwidth of operation, and exhibiting minimal absorption losses limited only by the intrinsic loss of the metallic substrate. These principles can be used for many frequency regimes (from GHz and lower, all the way to optical).

Surface-plasmon index guided (SPIG) waveguides and surface-plasmon effective index guided (SPEIG) waveguides

An optical modulator includes a crystal structure that exhibits polaritonic or excitonic behavior. A shock wave propagates through the crystal structure so as to optically modulate and manipulate a light signal propagating in the crystal structure.

Coherent generation, conversion, and modulation of electromagnetic radiation using shock waves or solitons propagating through polaritonic or excitonic materials

A device for converting frequency of electromagnetic radiation includes a nonlinear medium that forms a moving grating in the nonlinear medium by introducing at opposite ends of the nonlinear medium a first set of electromagnetic radiation having varying frequencies. Electromagnetic radiation is inputted into the nonlinear medium at a first frequency and extracted at a second frequency from the nonlinear medium. The moving grating in the nonlinear medium allows for electromagnetic radiation to be converted into the second frequency.

Shock-wave modulation and control of electromagnetic radiation

Electromagnetic radiation is input into a photonic crystal having a shock wave propagating within, wherein interactions between the shock wave and the incident electromagnetic radiation provide for the modification of frequency and bandwidth associated with input electromagnetic radiation. Modifications in frequency of the electromagnetic radiation are on the order of the gap size with 100% efficiency in some cases. Additionally, the bandwidth associated with the electromagnetic radiation is increased or decreased by orders of magnitude based on such interactions. High amplitudes are trapped at the shock front for a controllable period of time, allowing for the controlled manipulation of pulses of light. Lastly, the incorporation of deliberately designed crystal defects and non-linear materials results in the conversion of all the energy in the defect band upwards in frequency if the highest group velocity is less than the shock wave speed.

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Pine Island, MN, United States of America

Evan J Reed