# Engineering integrated photonics for heralded quantum gates

@article{Meany2015EngineeringIP, title={Engineering integrated photonics for heralded quantum gates}, author={Thomas Meany and Devon N. Biggerstaff and Matthew A. Broome and Alessandro Fedrizzi and Michael Delanty and Michael J. Steel and Alexei Gilchrist and Graham D. Marshall and Andrew G. White and Michael J. Withford}, journal={Scientific Reports}, year={2015}, volume={6} }

Scaling up linear-optics quantum computing will require multi-photon gates which are compact, phase-stable, exhibit excellent quantum interference, and have success heralded by the detection of ancillary photons. We investigate the design, fabrication and characterisation of the optimal known gate scheme which meets these requirements: the Knill controlled-Z gate, implemented in integrated laser-written waveguide arrays. We show device performance to be less sensitive to phase variations in the…

## 19 Citations

### Femtosecond laser direct writing of an integrated path-encoded CNOT quantum gate

- PhysicsOptical Materials Express
- 2019

Femtosecond lasers enable three-dimensional direct writing of waveguides inside bulk transparent materials and have been applied to the fabrication of integrated photonic quantum logic gates. Up to…

### Femtosecond Laser Direct Writing of Integrated Photonic Quantum Chips for Generating Path-Encoded Bell States

- PhysicsMicromachines
- 2020

This work demonstrates the FLDW of integrated photonic quantum chips composed of one Hadamard gate and one CNOT gate for generating all four path-encoded Bell states and shows that the average fidelity of the reconstructed truth table reaches as high as 98.8 ± 0.3%.

### Femtosecond laser micromachining for integrated quantum photonics

- PhysicsNanophotonics
- 2021

Abstract Integrated quantum photonics, i.e. the generation, manipulation, and detection of quantum states of light in integrated photonic chips, is revolutionizing the field of quantum information in…

### Microscopic characterisation of laser-written phenomena for component-wise testing of photonic integrated circuits

- Physics
- 2018

Photonic integrated circuits (PICs) directly written with a femtosecond laser have shown great potential in many areas such as quantum information processing (QIP). Many applications, like…

### Towards quantum applications based on photonic entanglement

- Physics
- 2017

A novel fully wave-guided, high performance photonic entanglement source is presented, able to generate hyper-entangled states in the observables of polarization and energy-time by means of a nonlinear Sagnac loop, promising scalable and potential real device applications with limited resources and simplified detection schemes.

### Hybrid laser written waveguides in fused silica for low loss and polarization independence.

- PhysicsOptics express
- 2017

This work demonstrates the inscription of hybrid waveguides in fused silica at a pulse repetition rate of 1MHz that fulfill both low insertion loss and low polarization dependence criteria.

### Trimming laser-written waveguides through overwriting.

- PhysicsOptics express
- 2020

This work shows how the use of device trimming can be used in the manufacture of directional couplers by overwriting the laser-written structure to alter the coupling ratios.

### Component-wise testing of laser-written integrated coupled-mode beam splitters.

- PhysicsOptics letters
- 2019

This work demonstrates a solution for component-wise testing of coupled-mode IBSs without limitations on component location and PIC architectures using imaging of an individual IBS with a custom-built multifunctional adaptive optical microscope and the calculation of its beam-splitting ratio through numerical modelling.

### The quantum technologies roadmap: a European community view

- PhysicsNew Journal of Physics
- 2018

Within the last two decades, quantum technologies (QT) have made tremendous progress, moving from Nobel Prize award-winning experiments on quantum physics (1997: Chu, Cohen-Tanoudji, Phillips; 2001:…

### Integrated path-encoded CNOT quantum gate fabricated by femtosecond laser direct writing

- PhysicsFrontiers in Optics + Laser Science APS/DLS
- 2019

We demonstrate the fabrication of an integrated path-encoded CNOT quantum gate inside glass using femtosecond laser direct writing. The quantum interference visibility can reach 0.97 and average…

## References

SHOWING 1-10 OF 47 REFERENCES

### Silica-on-Silicon Waveguide Quantum Circuits

- PhysicsScience
- 2008

These results show that it is possible to directly “write” sophisticated photonic quantum circuits onto a silicon chip, which will be of benefit to future quantum technologies based on photons, including information processing, communication, metrology, and lithography, as well as the fundamental science of quantum optics.

### Integrated photonic quantum gates for polarization qubits

- PhysicsNature communications
- 2011

The first integrated photonic controlled-NOT (CNOT) gate for polarization-encoded qubits is demonstrated, demonstrating its high fidelity to the expected one and the ability of this gate to transform separable states into entangled ones and vice versa.

### High-fidelity quantum photonics on a programmable integrated circuit

- Physics
- 2014

It is found that programmability dramatically improves device tolerance to fabrication imperfections and enables a single device to implement a broad range of both quantum and classical linear optics experiments.

### Hybrid photonic circuit for multiplexed heralded single photons

- Physics
- 2014

A key resource for quantum optics experiments is an on‐demand source of single and multiple photon states at telecommunication wavelengths. This letter presents a heralded single photon source based…

### Laser written waveguide photonic quantum circuits.

- PhysicsOptics express
- 2009

Directional couplers are characterized--the key functional elements of photonic quantum circuits--and it is found that they perform as well as lithographically produced waveguide devices.

### Phase-controlled integrated photonic quantum circuits.

- PhysicsOptics express
- 2009

A key proof-of-principle demonstration of an externallycontrolled photonic quantum circuit based upon UV-written waveguide technology and non-classical interference of photon pairs in a Mach-Zehnder interferometer constructed with X couplers in an integrated optical circuit.

### Realization of a Knill-Laflamme-Milburn controlled-NOT photonic quantum circuit combining effective optical nonlinearities

- PhysicsProceedings of the National Academy of Sciences
- 2011

A heralded controlled-NOT (CNOT) gate for scalable quantum computation using a photonic quantum circuit to combine two such nonlinear elements and should be useful for on-demand entanglement generation and purification.

### Waveguide photon-number-resolving detectors for quantum photonic integrated circuits

- Physics
- 2013

Quantum photonic integration circuits are a promising approach to scalable quantum processing with photons. Waveguide single-photon-detectors (WSPDs) based on superconducting nanowires have been…

### Three-dimensional quantum photonic elements based on single nitrogen vacancy-centres in laser-written microstructures

- PhysicsScientific reports
- 2013

This work fabricates complex assemblies of 3D quantum optical structures for the first time by using two-photon laser lithography and a photoresist containing nanodiamonds including nitrogen vacancy-centers to generate single photon generation, collection, and transport.

### A scheme for efficient quantum computation with linear optics

- PhysicsNature
- 2001

It is shown that efficient quantum computation is possible using only beam splitters, phase shifters, single photon sources and photo-detectors and are robust against errors from photon loss and detector inefficiency.