qLDPC Researcher

Job Title: qLDPC Theorist – Neutral Atom Quantum Computing

Location: Tokyo, Japan (Hybrid – up to 1/3 of year remote from your home country)

Employment Type: Full-time

Experience Level: Flexible. Fresh PhD or Postdoc / Industry Experience

About the Compan

yWe are a well-funded, venture-backed startup building one of the most scalable paths to fault-tolerant quantum computing: neutral atom quantum computers . Founded in April 2025 and backed by top-tier investors including Quantonation, Beyond Next Ventures, and ANRI, we have also secured a multi-billion-yen NEDO grant from the Japanese government . Our team of ~50 includes world-leading researchers from Kyoto University and the Institute for Molecular Science, and we are on track to complete a fault-tolerant quantum computer prototype by FY2027

.
The Opportuni

tyWe are seeking a qLDPC Theorist to join our core theory team. This is a high-impact role where you will own the development of quantum error correction architectures for our neutral atom platform - directly shaping the code design, logical operations, and decoding strategies that will underpin our fault-tolerant syste

m.
You will report to our Head of Theory and collaborate closely with experimentalists building ytterbium-based optical tweezer arrays. This is a rare opportunity to see your theoretical work implemented in hardware from the ground

up.
What You'l

• l DoqLDPC Code Development: Design, analyze, and optimize high-rate qLDPC code families (e.g., generalized bicycle, hypergraph product, lifted product codes) suited to neutral atom architectures with sparse connecti
• vityLogical Operations: Implement fault-tolerant logical operations, including lattice surgery, code switching, and transversal gate schemes for qLDPC c
• odesAddressable Gates: Develop schemes for addressable gates in LDPC codes under realistic qubit connectivity constraints and Rydberg blockade limitat
• ionsDecoding: Design and simulate decoding algorithms (BP+OSD, belief propagation variants, and novel approaches) under circuit-level noise models; estimate logical error rates and fault-tolerance thresholds using Monte Carlo met

hods
What You'll

BringEssen

• tial:PhD in Physics, Mathematics, Computer Science, or a related field, with a focus on quantum error corre
• ctionDeep expertise in qLDPC codes (code construction, distance bounds, deco
• ding)Experience with fault-tolerant quantum circuits and logical gate implementa
• tionsProficiency in simulation frameworks (e.g., Stim, Python,
• C++)Strong publication record in quantum error correction or related

areasDesir

• able:Experience with neutral atom or Rydberg-based quantum comp
• utingFamiliarity with lattice surgery, code switching, or addressable gate sc
• hemesBackground in algebraic coding theory, information theory, or condensed matter ph

ysics
What We

• OfferCompetitive Salary – benchmarked against top quantum roles in US/Europe
• /JapanSignificant Equity – be an owner in a company with global am
• bitionFull Relocation Support – visa, flights, temporary housing, and help finding long-term accommo
• dationHybrid Work Model – up to 4 months per year remote from your home country; the rest on-site in
• TokyoWorld-Class Team – work alongside pioneers in neutral atom QEC from Kyoto University a
• nd IMSHigh Impact – your research will directly inform hardware architecture, not just sit in a j
• ournalTokyo Location – vibrant city with a strong expat community and growing quantum eco

system
About Our

CultureWe are a collaborative, low-ego team driven by the challenge of making fault-tolerant quantum computing a reality. We value intellectual curiosity, rigorous thinking, and the ability to bridge theory with practical implementation. The theory team is growing, and you will have genuine ownership over your research direction within the company's technical r

oadmap.
How

to ApplyIf you are excited about building the foundation of a scalable neutral atom quantum computer, we want to hear f

rom you.Please apply to this advert, or send your CV and a brief cover letter to jos@ct-

19.co.uk