Lancaster University Quantum Technology Centre

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Lancaster University Quantum Technology Centre

Lancaster University Quantum Technology Centre

Quantum information

Our research group focuses on developing novel solutions to the practical application of quantum information systems, by combining the growth of semiconductor nanostructures with nano-scale device processing, and novel optoelectronic control and measurement schemes.

The only commercial application of quantum information currently is quantum key distribution (QKD). QKD uses a negative rule imposed by quantum mechanics; that certain measurements can’t be made without disturbing the system being measured. If a communication channel is setup correctly, we can detect eavesdropping attempts using this simple principle of quantum physics, guaranteeing the security of the system. Technology based on this idea has matured, but it is currently limited to point-to-point links using bulky and expensive hardware. To make more versatile systems that are compatible with fibre-based internet architecture (pictured below) we are developing new elements for processing quantum information.

 

To date, international research has proposed numerous schemes and systems to achieve more complex quantum operations, such as memory and repetition. Elaborate arrangements utilising the excitation of atomic ensembles in macroscopic crystals have demonstrated quantum memory, but scaling potential is lacking. Quantum dots have received much attention for use in devices as they are highly scalable and can be integrated into semiconductor technology. Electron-nuclear interactions can induce dephasing that is too strong for memory applications however, and cryogenic temperatures are typically required. In the group at Lancaster we are pioneering a solution to the problem of dephasing, using the GaSb/GaAs material system. This system shows promise for achieving telecoms wavelength compatibility and room temperature operation.

Theme contacts

  • Dr Robert Young
  • Dr Utz Roedig
  • Professor Henning Schomerus

 

Nanofabrication facilities

JEOL JBX-5500FS

JEOL JBX-5500FS High resolution electron beam lithography system with a beam diameter of 2nm. Using 50 KeV fine electron beam, line widths down to 10nm are achievable. The stage is positioned and controlled using laser interferometer which gives the line stitching accuracy of 40nm.

Specifications:

  • Electron emitter: TFE (ZrO/W)
  • Acceleration Voltage: 50 keV
  • Minimum beam diameter: 2 nm
  • Minimum line width: 10 nm
  • Beam current: 30 pA – 20 nA
  • Field size: 100 μm, 1000 μm
  • Beam scanning speed: 12 MHz

SUSS MicroTec MJB4 Mask Aligner

SUSS MicroTec MJB4 Mask Aligner An optical mask aligner using a mercury dischage lamp for exposing patterns in photoresist. Both front and back side alignment can be performed.

Oxford Instruments Plasma Pro NGP80 ICP

Oxford Instruments Plasma Pro NGP80 ICP Plasma deposition of thin films of SiO2 and Si3N4.

The reactive gases used are SiH4, NH3, N2O and N2.

Oxford Instruments Plasmalab System 100

This system uses chlorine base chemistry to etch mainly III-V semiconducting materials. It has both the RIE and ICP sources and a load lock is used to transfer samples. Etching of the multilayers materials can be monitored using a laser interferometer.

Etchant gases are BF3 , Cl2 , CH4 , H2 , Ar, O2 and SF6.

Oxford Instruments Reactive Ion Etcher

Used for dry etching of Si, SiO2 and Si3N4.

Etchant gases are CHF3 , CF4 , O2 and Ar.

Moorfield Thermal Evaporator

A four source thermal evaporator for the deopsition of thin metallic films.

Moorfield Electron Beam Evaporator with Oxidation System

The electron source incorporates a rotating carousel with six crucuble positions for the deposition of thin metallic films. The deposition rate and film thickness are automatically controlled.

The system incorporates a custom chamber for the controlled oxidation of deposited films.

Moorfield Sputtering System

This system has a DC and an RF sputtering source. It is used for the thin film deposition of insulating materials and metals – including refractory metals that can be difficult to evaporate.

Allwin AccuThermo AW610 Rapid Thermal Annealer

This annealer uses quartz lamps to rapidly heat samples following a computer controlled temperature profile. Annealing up to 800°C can be done in atmospheres of forming gas, N2, O2 or Ar.

Diener Electronics Plasma Asher

This asher uses an O2 plasma to dry clean surfaces prior to film deposition and to remove photoresist residue.

TPT HB05 Ultra-sonic Wire Bonder

An ultra-sonic wire bonder to attach thin wire (typically 10 to 20 μm diameter) to bond pads on completed structures.

Contact Us

By post

Lancaster Environment Centre,
Lancaster University,
Lancaster, LA1 4YQ,
United Kingdom

By phone

LEC general office
+44 (0)1524 510082

Undergraduate Enquiries
+44 (0)1524 510249

Postgraduate Enquiries
+44 (0)1524 510476