[Under construction]2017 AFOSR MURIPO: Dr. Tristan Nguyen, Information Assurance and CybersecurityPI: Thomas Vidick, California Institute of TechnologyMURI Website
Research objectives: Quantum computers made of tens of qubits are becoming a tangible reality. Approaches based on ion trap quantum computing or superconducting devices offer a clear path towards hundreds. Testing such quantum devices poses a fundamental challenge: even using the most advanced methods, the most common tests, state and process tomography, become impractical beyond 10−20 qubits. There is currently no robust and scalable practical approach to testing quantum devices, creating major problems in terms of verifiability and trust.
The ultimate goal of this MURI is to develop scalable protocols to test, control and enable the secure, reliable use of arbitrary quantum devices. We aim to establish solid theoretical foundations for the trustworthy operation of large-scale quantum devices in the long term. We will develop a framework of interactive testing protocols by combining past successes of members of our team with new techniques from quantum complexity theory, quantum cryptography, and quantum information. Our research entails a strong interaction between theory and experiments. We will combine trapped ions with photonics to implement complex systems that can be used to test and validate the protocols and concepts developed in this MURI.
Our research is organized along three complementary directions:
(A) Certifying a single untrusted quantum device. The problem is to securely delegate a quantum computation to an untrusted quantum device via a classical interaction. We approach this by making cryptographic assumptions and placing reasonable physical restrictions on the device.
(B) Multiple quantum devices sharing entanglement. With multiple quantum devices, quantum computation can be delegated with stronger security guarantees—even certifying a computation with adversarial devices. We will develop protocols for entanglement testing, process tomography and other cryptographic applications.
(C) Turing tests for quantumness. We will introduce a systematic framework of classical benchmarks against which the quantum behavior of large scale quantum annealers and other special purpose quantum devices can be evaluated.
Impact on DoD capabilities: Our protocols, and their proofs of security, will establish the theoretical underpinnings for a network of interacting quantum devices. The resulting infrastructure for secure computation and communication will be of benefit to DoD and all participating actors. The experimental components of this MURI will lead to the development of medium-scale quantum devices that can be reliably used for quantum cryptography in a strongly adversarial environment.