Quantum Enhanced RF Components

Introduction: Since the invention of the microwave antenna, warfare has become overwhelmingly reliant on command, control, and communication (C3) systems using radio frequency (RF) signals to transmit information. As more countries develop and deploy advanced technologies, the bandwidth in which these technologies operate has become increasingly crowded. Additionally, new technologies are emerging that use low-level communication signals or rely on low-profile radar signatures. With our current RF technology, low-level signals are challenging to detect in a noisy and overcrowded frequency space, creating a blind spot that presents a key challenge for intelligence, surveillance, and reconnaissance (ISR) missions. Problem: As we anticipate the emergence of quantum technologies, such as superconducting circuits, few-photon RF signals will constitute a key basis for quantum communication, sensing, and computing. Like low-level classical RF signals, quantum RF signals with low-photon fluxes will be inherently difficult to measure, necessitating new form factors of detectors and amplifiers with high efficiencies and gain, low noise, and large operational bandwidths. The R&D within this SBIR Phase I could prove invaluable in developing the next generation of sensitive, low-noise RF devices. Technical Approach: In superconducting quantum circuits, qubit state information is read out via low-power microwave signals consisting of only a few photons. Thus, ultralow-noise microwave parametric amplification is critical to processing and transmitting these signals and is a key component of superconducting quantum processors. However, these parametric amplifiers (paramps) suffer from several key drawbacks, including sensitive operation and performance limitations (e.g., gain-bandwidth tradeoff and pump depletion) that limit their use and application to superconducting circuit experts in well-controlled laboratory environments. Parametric amplification is not restricted to the RF regime and has analogues in mechanical and optical frequencies. Additionally, the nonlinear optical community has made great strides in overcoming limitations in parametric amplification and frequency conversion (FC) using methods such as dispersion engineering, adiabatic amplification, and hybridization of nonlinear processes. We propose applying these novel optical techniques to the microwave regime to develop more robust, efficient, and broadband microwave parametric amplifiers for low-level RF detection. These improvements would aid quantum information science and communication by facilitating more robust quantum state readout and allowing superconducting paramps to see broader applications, including chemical sensing, astronomy, and radar.