15 PhD positions in the MSCA Doctoral Network PHOTONIQC - Building on Europe’s leadership in integrated quantum photonics to address scalability

Is the Job related to staff position within a Research Infrastructure?: No

Offer Description

15 PhD positions in the MSCA Doctoral Network PHOTONIQC - Building on Europe’s leadership in integrated quantum photonics to address scalability

Grant Agreement No. 10132868

Technologies for Scalable Quantum Computing Our distributed photonic quantum computing platform will use qubits encoded by single photons, deterministic single-photon sources, dense high-transmission chips, record-efficiency detectors, and new quantum algorithms. Together, these technologies form a pathway toward scalable and practical quantum computers.

PHOTONIQC unites leading European academic and industrial partners to train 15 Doctoral Candidates across theoretical, experimental, and industrial aspects of quantum technology.

How to apply: The separate job ads will open soon. A link will appear under each corresponding DC profile outlined below. The deadline for each position will vary - refer to the individual job ads for this information.

The 15 positions are distributed among the PHOTONIQC beneficiaries as follows:

DC1 Technical University of Denmark (DTU) - Prof Niels Gregersen: Design and modelling of highly efficient single-photon sources (SPSs)

The objective is to increase the efficiency of the micropillar SPS design beyond 98% extraction efficiency by exploiting suppression of the background emission. Expected results include (i) control of the background emission in a micropillar using a photonic bandgap effect resulting from concentric rings, (ii) a novel micropillar SPS design with ridges with extraction efficiency to a fiber above 98 % and (iii) a novel nanopost design at 780 nm with extraction efficiency above 70 %.

DC2 Technical University of Denmark (DTU) - Prof Niels Gregersen: Experimental demonstration of highly efficient SPSs

The objective of IRP2 is to fabricate and characterize highly efficient micropillar-based SPSs exploiting suppression of the background emission based on designs from IRP1. The devices will be optically characterized in terms of purity, efficiency and photon indistinguishability using resonant and dichromatic pumping schemes. Expected results include (i) Stark tuning of QD line and charge stabilization using electrical contacts, (ii) full QD population inversion >0.98 and (iii) pure single photon emission g(2)(0) < 0.01 using dichromatic pumping, (iv) demonstration of improved efficiency thanks to the background emission engineering and (v) demonstration of >0.99 indistinguishable photon emission.

DC3 Centre National de la Recherche Scientifique (CNRS) - Dr Pascale Senellart: Spin mediated linear cluster states with GaAs quantum dots

The objective is an experimental study of single spin in a GaAs QD in a cavity with manipulation, control and spin-photon entanglement. Expected results include (i) a deterministically fabricated SPS based on a droplet GaAs QD in a cavity, (ii) an experimental study of the spin coherence time using phonon-assisted excitation, and (iii) demonstration of spin-photon entanglement (with DC14).

DC4 French Alternative Energies and Atomic Energy Commission (CEA) - Dr Julien Claudon: Bright and tuneable source of indistinguishable single photons operating at 780 nm

The objective is the development of a tuneable source of indistinguishable photons operating at 780 nm. Wavelength tuneability will be achieved by leveraging the strain generated by a planar piezoelectric actuator integrated below the nanopost. The tasks include the design, fabrication and optical characterization. Expected results include (i) design of a broadband AlGaAs nanopost cavity operating at 780 nm (in collaboration with DTU), (ii) fabrication of an AlGaAs nanopost cavity embedding a GaAs QD, (iii) demonstration of strain-tuning of the QD emission and (iv) demonstration of the efficient >70% emission of indistinguishable >90% photons at 780 nm.

DC5 Ruhr University (RUB) - Dr. Arne Ludwig: Growth of low-noise QD heterostructures

The objectives are to model, design, grow, and assess charge-tuneable QD heterostructures through optical and electrical methods to establish quantitative thresholds for low charge noise and to develop QD growth techniques suitable for various photonic structures. QDs will be embedded in an n-i-p or n-i-n diode structures, enabling charge control and Stark tuning of the emission to photonic cavity resonance. Ensemble and single optical properties will guide optimization at RUB across high-electron-mobility heterostructures, quantum wells and tuneable QD devices. Expected results include (i) ultra-low-noise and low-density QD heterostructures deterministically coupled to thin electron reservoirs that are located in the standing wave antinodes of the anticipated photonic cavities, (ii) adaption of the QD emission wavelength to Rb memory cell, (iii) a methodology to calculate and determine an optimal tunnel coupling to a charge reservoir and (iv) a “sample compare” standard and clear roadmap on how to mitigate charge noise in MBE grown SPSs.

DC6 National Research Council (CNR) - Dr. Roberto Osellame: Development of low power dissipation large scale integrated quantum photonic circuits

The objectives are design, fabrication and calibration of vacuum-sealed integrated photonic circuits directly written in glass by fs laser pulses. This achievement will be key to scale the number of phase shifters that can be integrated on a single chip without having to dissipate a large amount of heat. In addition, this result will reduce the thermal crosstalk, thus increasing the accuracy of the implemented quantum transformation. In parallel, we will also reduce the size of the integrated photonic circuits by reducing the waveguide pitch, hence aiming at a largely improved chip transmission. Expected results include (i) implementation of a vacuum-sealed packaging for integrated photonic chips, (ii) proof of a reduction of dissipated power, for a 2π phase shift, below 10 mW per thermal shifter and (iii) demonstration of a programmable photonic chip with at least 10 optical modes fully packaged with optical fibers and electrical connections with a total transmission >85%.

DC7 Single Quantum (SQ) - Dr. Mario Casteneda: High fidelity photon number resolving detectors

The objectives are to design, fabricate and test superconducting nanowire single-photon detectors (SNSPDs) with photon number resolving capability. It has been proposed that the risetime of the detection pulse of SNSPDs is photon number dependent. However, no readout schemes are currently available that are suitable for implementation in a quantum computer. The DC will work on developing readout schemes and electronics to measure directly the rise time of the detection pulse. Furthermore, the fidelity is highly dependent on the quantum efficiency for single photons, for example if the efficiency of 90%, the fidelity for a two-photon event is only 81%. Therefore, the DC will work on improving the quantum efficiency and bring it close to unity. For fault tolerant photonic quantum computers thousands, if not millions, single-photon detectors will be needed. Therefore, the DC will also work on establishing recipes for improving the yield of these high efficiency detectors. Expected results include (i) development of single-photon detectors with >95% efficiency at 900 and 1550 nm, (ii) development of wafer-scale fabrication techniques and recipes for detectors with >10% yield, (iii) demonstration of single-click photon number resolving measurements and (iv) new scientific insights through implementation in experiments. Experiments will involve quantum optical, quantum computational and correlative imaging experiments.

DC8 Technical University of Denmark (DTU) - Prof Niels Gregersen: System architecture for cluster state quantum computing

The objective is to define device performance requirements for applications using arbitrary photonic graph states. From this, we define device requirements as a function of network size, postselection probability, and graph-state structure. Expected results include (i) use of stabilizer formalism and imperfection modelling to link component performance with success rate and fidelity of obtained graph states of different topologies, (ii) evaluation of performance of different computational tasks using photonic graph states and (iii) study of alternative physical architectures for fusion-based quantum computation and the corresponding required device performance.

DC9 Quandela (QUA) - Dr. Boris Bourdoncle: Protocols for secure delegated quantum computing with QD sources and photonic chips

The objective is development of protocols for secure delegated quantum computing adapted to discrete-variable photonic platforms. The possibility to generate spin-photon entanglement at the source offers new avenues to delegate computations from a client to a server. The project will require adapting the protocol to the characteristics of the hardware to make it as resource-efficient and secure as possible. Expected results include (i) improvement of a protocol for blind delegated quantum computing where the client manipulates an attenuated laser pulse, (ii) design of a protocol for secure delegated variational quantum algorithms (VQAs) and (iii) implementation of the protocol (in cooperation with DC14).

DC10 University of Edinburgh (EDI) - Prof Elham Kashefi: Zero‑trust verification for delegated & distributed photonic quantum computing

The objectives are exploration of existing and new optimized methods for design of secure photonic quantum circuits and certification of their functioning under noise and imperfections. We will adapt existing methods for the characterization of post-selected photonic circuits, and also for photonic graph (stabilizer) states. Expected results include (i) adapted zero-trust framework for the purpose of masking of photonic quantum computation protocols, (ii) improved generation of arbitrary graph states of a few qubits in a linear-optical platform, certifying their fidelity with an exploration of computational applications and (iii) adaptation of trap-based methods to account for experimental imperfections: limited photonic indistinguishability, photon loss, imperfections in circuit components.

DC11 International Iberian Nanotechnology Laboratory (INL) - Dr. Leonardo Novo: Photon distinguishability and the simulability of linear optics

The objectives are to develop efficient tomography protocols for partially distinguishable bosons and measures of bosonic indistinguishability. Expected results include (i) the development of more efficient protocols for tomography of photonic states prepared by linear optical interferometers and imperfect photon sources, (ii) the application to the characterization of unitary errors and particle distinguishability in photonic experiments, (iii) the connection of measures of photon indistinguishability to the complexity of simulation of linear optical experiments and (iv) the analysis of complexity of classical simulations of boson sampling with partial distinguishability and limited adaptivity.

DC12 Sapienza University of Rome (SAP) - Prof Fabio Sciarrino: Distributed quantum computing with photonic technologies

The objective is to implement distributed quantum computing based on SPSs and integrated photonics. The DC will first be trained on the design of quantum photonic architecture, schemes for distributed quantum computing with a specific focus on the photonics platform and further developing advanced photonic platforms (comprising high efficiency photon sources, integrated circuits interfaced with single modes fibers with path-polarization converters and single-photon detectors). The DC will then work on the implementation of distributed quantum computing with up to three nodes. Expected results include (i) assembly of an advanced photonic quantum computing platform distributed over 3 nodes (in cooperation with DC13), (ii) design of a blind quantum computing architectures with 3 nodes and (iii) implementation of the developed protocols.

DC13 Sapienza University of Rome (SAP) - Nicolo Spagnolo: Experimental demonstration of variational quantum algorithms (VQAs) in integrated photonic platforms

The objective is to perform experimental demonstration of VQAs in an advanced photonic platform. The DC will be trained in the relevant theoretical (VQAs) and experimental skills (advanced photonic comprising high efficiency SPSs, integrated circuits and single-photon detectors) via secondments at three partners. The DC will then demonstrate the application of a variational approach to optimize the implementation of quantum computing primitive within the assembled system. Expected results include (i) assembly of an advanced photonic quantum computing platform (in cooperation with DC12), (ii) identification and optimization of variational quantum approaches to obtain a specifically tailored toolbox for photonic quantum computing apparata including noise models and (iii) implementation of the identified toolbox to control and program the assembled photonic platform for quantum computing applications.

DC14 Centre National de la Recherche Scientifique (CNRS) - Dr. Olivier Krebs: Experimental delegated quantum computing protocols with linear cluster states

The objective is to experimentally demonstrate quantum computing protocols with linear cluster states generated with InGaAs QDs operating at 925 nm. After working on maximizing the cluster state length and dimension as well as the photon indistinguishability, we will implement small scale quantum information processing protocols using the generated states. We will target both quantum communication protocols and quantum computing protocols. Expected results include (i) enhanced rate, fidelity and length photonic cluster states based on spin-photon or linear gates, (ii) experimental demonstration of a quantum communication protocol based photonic cluster states, (iii) demonstration of delegated and/or secure quantum computing protocol with photonic cluster states at 925 nm and (iv) exploration of quantum frequency conversion for long distance demonstrations.

DC15 Sorbonne University (SU) - Prof Julien Laurat: Interfacing a QD SPS with a cold-atom-based quantum memory

The objective is to demonstrate on-demand storage and retrieval of photons from a QD SPS in an atomic quantum memory for applications in quantum networks. Based on prior works of the host with 90% storage-and-retrieval efficiency in a Rb large atomic ensemble, the quantum memory will be optimized to efficiently store the short temporal wavepacket of the single photons via control pulse shaping. Expected results include (i) efficient storage and on-demand read out of photons from a QD source in atomic quantum memory, (ii) demonstration that the single-photon purity of the photons retrieved from the memory is unchanged from the input and (iii) demonstration that the indistinguishability of the photons retrieved from the memory is higher than the input due to mode filtering.

Where to apply

Website: http://www.electro.dtu.dk/photoniqc

Requirements

Research Field: Engineering

Education Level: Master Degree or equivalent

Work Location(s)

Number of offers available: 3

Company/Institute: Technical University of Denmark DTU

Country: Denmark

City: Kongens Lyngby

Postal Code: 2800

Number of offers available: 2

Company/Institute: Centre National de la Recherche Scientifique CNRS

Country: France

City: Palaiseau

Postal Code: 91120

Number of offers available: 1

Company/Institute: French Alternative Energies and Atomic Energy Commission CEA

Country: France

City: Grenoble

Postal Code: 38000

Number of offers available: 1

Company/Institute: Ruhr University RUB

Country: Germany

City: Bochum

Postal Code: 44801

Number of offers available: 1

Company/Institute: National Research Council CNR

Country: Italy

City: Milan

Postal Code: 20133

Number of offers available: 1

Company/Institute: Single Quantum SQ

Country: Netherlands

City: Delft

Postal Code: 2628 ER

Number of offers available: 1

Company/Institute: Quandela QUA

Country: France

City: Massy

Postal Code: 91300

Number of offers available: 1

Company/Institute: University of Edinburgh EDI

Country: United Kingdom

City: Edinburgh

Postal Code: EH8 9YL

Number of offers available: 1

Company/Institute: International Iberian Nanotechnology Laboratory INL

Country: Portugal

City: Braga

Postal Code: 4715-330

Number of offers available: 2

Company/Institute: Sapienza University of Rome SAP

Country: Italy

City: Rome

Postal Code: 00185

Number of offers available: 1

Company/Institute: Sorbonne University SU

Country: France

City: Paris

Postal Code: 75006

Contact

City: 2800 Kongens Lyngby

Website: https://electro.dtu.dk/

Street: Ørsteds Plads Bygning 343

Postal Code: 2800

E-Mail: lestr@dtu.dk

Phone: 30721632