Resonant tunneling diodes (RTDs) have come fullcircle in the past 10 years after their demonstration in the early 1990s as the fastest roomtemperature semiconductor oscillator, displaying experimental results up to 712 GHz and fmax values exceeding 1.0 THz [1]. Now the RTD is once again the preeminent electronic oscillator above 1.0 THz and is being implemented as a coherent source [2] and a selfoscillating mixer [3], amongst other applications. This paper concerns RTD electroluminescence – an effect that has been studied very little in the past 30+ years of RTD development, and not at room temperature. We present experiments and modeling of an ntype In0.53Ga0.47As/AlAs doublebarrier RTD operating as a crossgap light emitter at ~300K. The MBEgrowth stack is shown in Fig. 1(a). A 15μmdiammesa device was defined by standard planar processing including a top annular ohmic contact with a 5μmdiam pinhole in the center to couple out enough of the internal emission for accurate freespace power measurements [4]. The emission spectra have the behavior displayed in Fig. 1(b), parameterized by bias voltage (VB). The long wavelength emission edge is at = 1684 nm  close to the In0.53Ga0.47As bandgap energy of Ug ≈ 0.75 eV at 300 K.more »
This content will become publicly available on May 1, 2023
Communication Trade Offs in Intermediate Qudit Circuits
Quantum computing promises speedup of classical algorithms in the long term. Current hardware is unable to support this goal and programs must be efficiently compiled to use of the devices through reduction of qubits used, gate count and circuit duration. Many quantum systems have access to higher levels, expanding the computational space for a device. We develop higher level qudit communication circuits, compilation pipelines, and circuits that take advantage of this extra space by temporarily pushing qudits into these higher levels. We show how these methods are able to more efficiently use the device, and where they see diminishing returns.
 Award ID(s):
 2016136
 Publication Date:
 NSFPAR ID:
 10338373
 Journal Name:
 2022 IEEE 52nd International Symposium on MultipleValued Logic (ISMVL)
 Page Range or eLocationID:
 43 to 49
 Sponsoring Org:
 National Science Foundation
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