Connects early optical quantum-gate experiments with the effort to manufacture large photonic quantum computers, now guiding PsiQuantum’s strategy and partnerships as executive chairman.
arXiv / NaturePsiQuantumO’Brien’s work spans the laboratory demonstration of an optical logic gate and the organization of a company around photonic quantum computing. The controlled-NOT experiment is a specific early result: it produced entangled photon states using an optical circuit, with limitations inherent to its probabilistic operation. PsiQuantum extends the photonic approach toward semiconductor manufacturing and large systems. His February 2026 move to executive chairman identifies a strategic role; it should not be confused with an ongoing chief executive title.
PsiQuantumarXiv / NatureThe work behind the recognition
Work, in context- 2003
Demonstrating an optical controlled-NOT gate
Coauthored an all-optical controlled-NOT gate experiment that produced all four Bell states. The demonstrated gate was probabilistic, an important qualification for its use in scalable computation.
Coauthor of the probabilistic optical controlled-NOT experiment; shared experimental credit.
Source-supported recordarXiv / Nature - 2016
Co-founding PsiQuantum
Helped found PsiQuantum to pursue large-scale photonic quantum computing. In February 2026 he became executive chairman, with responsibilities spanning strategy, the board and key partnerships.
Company co-founder and executive chairman; strategic and board responsibilities rather than sole hardware invention.
Source-supported recordPsiQuantum
Keep in perspective
Company-scale goals are presented as an ongoing effort, not as a delivered fault-tolerant computer.
The evidence map
Both views link each contribution to its sources. Choose a contribution on the map or read them all in the list.
Demonstrating an optical controlled-NOT gate
Demonstration of an all-optical quantum controlled-NOT gate
Supports: Coauthorship and experiment; journal publication Nature 426, 264 (2003)
Published 8 Mar 2004 · Checked 19 Sept 2026Credit & limits: Coauthor of the probabilistic optical controlled-NOT experiment; shared experimental credit.
Read the full contribution| Contribution | Evidence & what it supports | Credit & limits |
|---|---|---|
| Demonstrating an optical controlled-NOT gate2003 | Primary paperDemonstration of an all-optical quantum controlled-NOT gate Coauthorship and experiment; journal publication Nature 426, 264 (2003) Published 8 Mar 2004 · Checked 19 Sept 2026 | Coauthor of the probabilistic optical controlled-NOT experiment; shared experimental credit. |
| Co-founding PsiQuantum2016 | Company recordPsiQuantum Appoints Victor Peng as Interim CEO, Co-Founder Jeremy O’Brien to Become Executive Chairman Executive-chairman appointment, company founding and strategic responsibilities Published 10 Feb 2026 · Checked 19 Sept 2026 | Company co-founder and executive chairman; strategic and board responsibilities rather than sole hardware invention. |
Follow the evidence
2 sourcesPrimary papers, institutional records and attributed announcements. Each source supports the claims linked above.
- PsiQuantumCompany record
PsiQuantum Appoints Victor Peng as Interim CEO, Co-Founder Jeremy O’Brien to Become Executive Chairman
Executive-chairman appointment, company founding and strategic responsibilities
Published 10 Feb 2026 · Checked 19 Sept 2026 - arXiv / NaturePrimary paper
Demonstration of an all-optical quantum controlled-NOT gate
Coauthorship and experiment; journal publication Nature 426, 264 (2003)
Published 8 Mar 2004 · Checked 19 Sept 2026