Superconducting photonic cavity with engineered cubic nonlinearity for microwave-to-optical conversion (X(2)-M2O)
Abstract
This proposal addresses CQTS topic 1: quantum state transfer (QST) from microwave to optical frequencies. We propose to co-integrate superconducting and photonic resonator circuits in a single device platform and establish a quantum interface between superconducting qubits and room temperature flying photon qubits. Our approach leverages high frequency resonators oscillating at ~10GHz to directly transfer quantum state between microwave and optical carriers with minimal or no moving parts. The use of high frequency resonators boosts the transfer bandwidth and suppresses thermal noises by orders of magnitudes comparing to ~MHz mechanical transducers. However, challenges lie in device scaling to small modal volume for higher coupling rate and retaining high circulating optical power for enhanced co-operativity, particularly at cryogenic temperatures where photonics and superconductivity meet. We propose to address these challenges by taking the following systematic approaches: 1) operate the device in superfluid Helium to leverage the extremely high thermal conductance of superfluid and the high fridge cooling power at 1K; 2) utilize engineered cubic nonlinearity (x(^2)) to allow the conversion of 10 GHz microwave photon to optical photons via a single-pump three wave mixing process which results in low added thermal noises; 3) further reduce the pump power delivered to cryogenic stage by utilizing triple resonant structure in which the input, pump, and output modes all have high Q resonance; 4) impedance match conversion stages for maximized efficiency and bandwidth and minimum added noises. We engineer for the desired x(^2) nonlinearity with AlN microphotonic resonators. AlN has a non-centrosymmetric crystal that enables both electro-optic and piezoelectric properties, allowing for two classes of microwave-to-optical (M2O) converters: piezo-opto-mechanical (POM) and electro-optical (EO) converters, both capable of up-converting 10 GHz microwave photons but with somewhat complementary performances: POM converters offer higher vacuum coupling rate mediated by phonon mode, whereas EO converters promise high power handling, ease of integration, but have lower vacuum coupling rate due to larger modal volume. We will focus in year 1 on transducer development for realizing coherent state transfer in the classical regime and aim for high on-chip efficiency (>50%). At the end of year 1, we will down select from two proposed transduction approaches (POM versus EO) and choose the most promising scheme for the follow-on quantum state transfer (QST) demonstration. From Year 2 through Year 4, as we further advance our transducers for high system efficiency, we will mostly focus on QST demonstration. Depending on the achievable system efficiency and noise levels, we will implement three generations of quantum frequency converters. The 1st generation device will realize microwave-optical modes entanglement even with low system conversion efficiency by operating the M2O in parametric down-conversion mode with a blue detuned pump and heralding using classical communication channel. The 2nd generation converter will operate the M2O converter with a normal red-detuned pump and will achieve QST through teleportation in addition to the heralding necessary to achieve the entanglement of generation 1. Our ultimate goal is the 3rd generation converter which will achieve state transfer between two microwave modes through an optical link. Eventually, we will realize this type of transfer without heralding if the entire system reaches sufficient high efficiency (>50%). We will inject various microwave states prepared by our superconducting system and verify the quantum state-transfer by calibrating input-output fidelity.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Sep 11, 2018
- Source ID
- W911NF1810020
Entities
People
- Hongxing Tang
Organizations
- Army Contracting Command
- National Security Agency
- Yale University