MIT Lincoln Laboratory Quantum Work Explained

MIT Lincoln Laboratory's quantum program spans superconducting qubits, trapped ions, and diamond sensing, with the SQUILL foundry supporting outside groups.

MIT Lincoln Laboratory quantum research at a glance

MIT Lincoln Laboratory is a federally funded research and development center in Lexington, Massachusetts, that runs a roughly 200-person quantum effort across computing, interconnects, and sensing. Dan Ripin, head of the Advanced Technology Division, described that program in a talk published by MIT, and the transcript covers the platforms, the foundry access model, and two field systems.

The lab sits on Hanscom Air Firebase and reports about 4,500 staff. It began in 1951, growing out of the MIT Radiation Laboratory, and its original mission was air defense against Soviet bombers approaching over the North Pole.

Lincoln Laboratory was established in 1951 under MIT's sponsorship and grew out of the MIT Radiation Laboratory. Its work on the Semi-Automatic Ground Environment air defense system also produced real-time computing and magnetic core memory. The MITRE Corporation was spun off from the lab to acquire that system, and MITRE remains a separate organization today.

The three quantum workstreams at Lincoln Laboratory

Lincoln Laboratory divides its quantum research into three areas: quantum computing, quantum interconnects and communication, and quantum sensing. Ripin described sensing as the nearest-term path to field impact, while computing and networking are longer-horizon efforts tied to campus collaborations.

Leadership named in the talk includes Mollie Schwartz and Daniel Braschi on computing, with Jonilyn Yoder and Kyle Serniak also involved. Scott Hamilton and Ben Dixon lead interconnects and communication. Braschi leads sensing.

The three areas share fabrication and detector capabilities developed for other programs. Superconducting nanowire single-photon detectors built with MIT professor Karl Berggren's group illustrate that overlap.

Superconducting qubits and trapped ions in one foundry

Lincoln Laboratory builds superconducting qubit devices in its own 8-inch wafer fabrication line, which runs a 90-nanometer node process. The facility is a secure foundry, a requirement that matters for defense applications. The lab reports it has used this equipment for roughly 20 to 25 years with collaborators including MIT professor Will Oliver, who began his career at Lincoln Laboratory.

Superconducting qubit circuits are aluminum-based. The lab extended its process to three tiers to simplify room-temperature readout and control of the devices. Extending the metal stack this way is a packaging and signal-routing change, not a change to the underlying qubit physics.

The second platform integrates trapped ions with photonics on a wafer. That work combines ion traps with integrated photonics, integrated electronic readout, and single-photon-sensitive detectors for reading out quantum states. MIT professor Ike Chuang and Lincoln Laboratory's John Chiaverini are named as participants.

A 2022 Lincoln Laboratory review of its quantum information and integrated nanosystems work documents the same three-platform framing of superconducting qubits, trapped ions, and nitrogen-vacancy centers.

The SQUILL foundry and how outside groups get access

SQUILL is the superconducting qubit multiuser process that lets external research groups design devices into Lincoln Laboratory's fabrication line. Ripin said more than 30 research groups around the country were designing into the process at the time of the talk, an arrangement he described as a way to support the wider national quantum ecosystem rather than only in-house programs.

The program's START agreement with the Laboratory for Physical Sciences, reported in 2022, committed Lincoln Laboratory to providing a superconducting qubit fabrication process to LPS and to universities, with the option to involve companies as well.

Access matters because the tooling is hard to replicate. A group that cannot run a 90-nanometer superconducting process in-house can still test a design through a shared line, and Lincoln Laboratory is unusual in offering that on a secure, onshore fab.

The lab has made similar arrangements available in trapped-ion and nitrogen-vacancy diamond work. A US Department of Energy listing of quantum user facilities notes that access terms differ by program, so groups should check current eligibility rather than assume a single application route.

Quantum interconnects, fiber links, and what they demonstrated

Quantum interconnects matter for two jobs: linking separate quantum computers into one larger machine, and distributing quantum states over distance. Lincoln Laboratory runs a physical optical fiber link from Scott Hamilton's lab to MIT campus, reaching the groups of Dirk Englund, Ike Chuang, and Misha Lukin at Harvard.

That Boston-area link was used to demonstrate quantum state distribution and storage together at record fidelity, according to Ripin's account. The claim covers entanglement distribution over installed fiber with a storage element at the far end, not a deployed network.

Photonic interconnect work also connects to the same detector technology used in the lab's free-space laser demonstrations. Those detectors are the enabling component when the signal is a handful of photons.

Quantum sensing reached the field first

Sensing is the part of the portfolio Lincoln Laboratory expects to reach operational use soonest. Ripin said the lab sees near-term impact there for national security and other applications, ahead of fault-tolerant computing.

The example he gave is a nitrogen-vacancy diamond vector magnetometer flown in a package slung under a helicopter. Nitrogen-vacancy centers are defects in diamond whose spin states respond to magnetic fields, which makes them usable as field sensors at room temperature. The test asked whether a vector magnetometer could hold position better than a state-of-the-art inertial navigation system when GPS is denied. Ripin reported better positioning performance with the magnetometer than with the inertial system, without publishing numbers in the talk.

Fielding the payload required coordination with local police because of how the package looked in flight. That detail is procedural, but it signals that this was an outdoor flight test rather than a bench measurement.

How the detectors, lithography, and history connect

Ripin tied the quantum program to earlier Lincoln Laboratory work that is still in use. He said the lab did pivotal work on 193-nanometer lithography, which underpinned semiconductor fabrication for decades. He also described a free-space laser communication link to the Moon demonstrated around 2013 or 2014, described at the time as the longest laser link ever made.

That lunar link relied on superconducting nanowire single-photon detectors fabricated both at Lincoln Laboratory and by Berggren's group on campus. The same detector class supports the lab's quantum readout work, so a capability built for one demonstration has been reused across the portfolio.

MIT and Lincoln Laboratory collaborations run the other way too. The lab describes itself as a place that takes campus research and moves it toward national security use, which is why quantum computing faculty and students appear in multiple projects described in the talk.

FAQ

• What is MIT Lincoln Laboratory's role in quantum research? It is a federally funded research and development center that builds quantum hardware for national security use and also opens its fabrication processes to outside groups. Its work covers superconducting qubits, trapped ions, quantum interconnects, and diamond sensing.

• What is the SQUILL foundry and who can use it? SQUILL is a multiuser superconducting qubit fabrication process at Lincoln Laboratory that outside research groups design into. Ripin said more than 30 groups around the country were designing into the process at the time of the talk, and the program began under an agreement with the Laboratory for Physical Sciences.

• What did the quantum magnetometer test show? A nitrogen-vacancy diamond vector magnetometer flew beneath a helicopter and was tested against a state-of-the-art inertial navigation system with GPS denied. Ripin said the magnetometer gave better positioning, but the talk did not present public numbers.

• Does Lincoln Laboratory work only on quantum computing? No. Computing, interconnects and communication, and sensing are separate workstreams, and Ripin named sensing as the nearest-term path to field impact. Computing and networking remain the longer-horizon efforts.

• Who leads the quantum effort at Lincoln Laboratory? Dan Ripin heads the Advanced Technology Division, which covers the quantum portfolio. Mollie Schwartz and Daniel Braschi lead quantum computing, Scott Hamilton and Ben Dixon lead interconnects and communication, and Braschi leads sensing.

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