Abstract: The invention relates to an apparatus configured to receive an input message via the first interface. The input message having a first layer structure and containing an information piece associated with the top layer of the first layer structure, extracting the information piece from the input message by passing the input message through a protocol stack associated with the first layer structure from bottom to top, examining the extracted information piece to obtain an examination result, generating an output message by passing the extracted information piece or an information piece generated on the basis of the extracted information piece through a protocol stack associated with a second layer structure from top to bottom, and sending the output message via the second interface. The generating and/or the sending of the output message are performed as a function of the examination result.

Abstract: A laser device includes a gain medium including a facet. The laser device includes a metasurface including a plurality of supercells. The metasurface is disposed on a substrate and configured to reflect and focus a first portion of light from the facet back to the gain medium as a feedback beam. The metasurface can be configured to reflect a second portion of the light as an output beam at an angle that is nonzero relative to a direction of the feedback beam. The metasurface can be configured to transmit a second portion of the light as an output beam through the metasurface away from the facet. The emission wavelength of the laser device can be tuned by translating the metasurface. The output beam can be collimated towards a fixed direction while tuning the wavelength.

Abstract: A laser device includes a gain medium including a facet. The laser device includes a metasurface including a plurality of supercells. The metasurface is disposed on a substrate and configured to reflect and focus a first portion of light from the facet back to the gain medium as a feedback beam. The metasurface can be configured to reflect a second portion of the light as an output beam at an angle that is nonzero relative to a direction of the feedback beam. The metasurface can be configured to transmit a second portion of the light as an output beam through the metasurface away from the facet. The emission wavelength of the laser device can be tuned by translating the metasurface. The output beam can be collimated towards a fixed direction while tuning the wavelength.

Abstract: A wireless communication device includes a quantum cascade laser (QCL) configured to generate a terahertz (THz) or microwave carrier signal. The QCL includes a laser waveguide, a laser optical gain medium incorporated in the laser waveguide, and at least one electrode. An antenna may be integrated with the electrode. The device may be a transmitter, the electrode configured to receive an input baseband signal, the QCL configured to couple the THz or microwave carrier signal and the input baseband signal into a THz or microwave communication signal, and the antenna configured to transmit the THz or microwave communication signal. The device may be a receiver, the antenna configured to receive a THz or microwave communication signal, and the QCL configured to de-couple the THz or microwave communication signal from the THz or microwave carrier signal into an output baseband signal.

Abstract: A wireless communication device includes a quantum cascade laser (QCL) configured to generate a terahertz (THz) or microwave carrier signal. The QCL includes a laser waveguide, a laser optical gain medium incorporated in the laser waveguide, and at least one electrode. An antenna may be integrated with the electrode. The device may be a transmitter, the electrode configured to receive an input baseband signal, the QCL configured to couple the THz or microwave carrier signal and the input baseband signal into a THz or microwave communication signal, and the antenna configured to transmit the THz or microwave communication signal. The device may be a receiver, the antenna configured to receive a THz or microwave communication signal, and the QCL configured to de-couple the THz or microwave communication signal from the THz or microwave carrier signal into an output baseband signal.