Fully photon operated transmistor / all-optical switch based on a layered Ge1Sb2Te4 phase change medium

[Display omitted] •Layered chalcogenide structure of epitaxial trigonal Ge1Sb2Te4 exploited.•Active optical Ge1Sb2Te4 nano-membranes in photonic device employed.•Devices based on Ge1Sb2Te4 suitable for telecommunication wavelength range.•Fully photon operated transmistor presented.•Physical and material considerations for new device concept discussed. We propose an alternative device concept which represents the foundation for future fully photon operated logic circuits based on an optically active medium. The device has the potential to decrease energy consumption and simultaneously to significantly increase computational operation speed. We call this all-optical switch device a “transmistor”, since in this alternative concept a controllable train of photon pulses (optical gate) initializes substantial changes of the optical transmittance of an optically active medium by inducing structural changes therein. First results of a fully photon operated prototype of a transmistor device based on a layered phase change Ge1Sb2Te4 nano-membrane are presented. The transmittance changes of the nano-membrane‘s material structure determine the transmitted optical power in the functionally arranged optical device.