Supply and Delivery of a Quantum high stability open cavity

University College Cork and Tyndall national Institute are seeking an open cavity apparatus which can be mounted in ad-hoc closed cycle cryostat with lowest temperature of operations below 10 Kelvin. The system will be operated in the context of a national facility for quantum technologies hosted at the Tyndall National Institute. The apparatus should be capable of actively correcting for the cryostat vibrations and allow for maintaining over long period of time (hours) effective high Q and finesse cavities implemented as described below. It should also allow to be operated in magnetic fields. The open cavity system with internal stability control we seek should allow to measure and extreme optically confine nanostructures/nanoparticle/defects in semiconductor system positioned on a flat ad-hoc mirror and allow to position a mirrored fiber on top of the nanostructure/nanoparticle/defect to form a high finesse cavity, so to obtain a high optical emission enhancement. The first systems investigated will include single Pyramidal quantum dot structures, NV centres, and defects in 2D materials. In general, the cavity range of operation will cover the visible to near infrared. The Qlibri Quantum high stability open cavity is a custom built system capable of delivering the required performances. It can be inserted in a bespoke optical cryostat which can operate at 4 Kelvin with an applied magnetic field. It has proven efficient vibration isolation and it provides positioning in the 1.5mmx1.5 mm range. The electronic controls allow to perform scanning imaging spectrometry, while allowing for XYZ cavity position control. The system is provided with an efficient cavity Length Lock system which guarantees optimal functioning in a relatively noisy environment such as a closed cycle cryostat. As a result sub-picometer optical stability is achieved even in “noisy” environments. The micro-cavity system features an ultra-high Finesse of up F greater than 10⁵ and at the same time mode volumes as low as V less than 2λ³. Quality factors can exceed Q greater than 10⁶. Purcell’s effects as high as 1000 could be achieved. The system comes also with unique highly reflective micromirrors (reflectivity greater than 99.999 per cent, RMS surface roughness less than 1nm, RoC down to 10nm) The control system allows to operate the whole system with a computer interface. Moreover the system can also be operated outside a cryostat, providing an ultra sensitive absorption microscope, implementing a fast scanning cavity microscopy of great value in the characterization of nanostructures, including plasmonic effects. Technical Reasons for Award without Prior Publication: As per Article 32 of EU Directive 2014/24, University College Cork wishes to avail of the negotiated procedure without prior publication because competition is absent for technical reasons. The purchase of the Qlibry open cavity apparatus will provide the ability to create custom cavities bespoke to a specific nanosystem, without the need for processing “on chip” high Q cavities. The vital aspect to enable this capability is an efficient feedback control system capable of counteracting the cryostat vibrations when operated at cryogenic temperatures, while still independently maintaining a high Q environment for the embedded nanostructure. It will also allow to scan the cavity over samples on which several quantum nanostructures are present, efficiently modify the cavity conditions and achieve optimum conditions, while maintaining the vibration suppression characteristics. No equivalent system is currently available on the market from alternative suppliers of cryogenic high stability open cavity instruments and no alternative supplier’s system can be purchased resembling the required performances.