Improving the Resolving Power of Ultraviolet to Near-Infrared Microwave Kinetic Inductance Detectors

This thesis significantly advances our understanding of noise processes in Microwave Kinetic Inductance Detectors (MKIDs), enabling the development of more efficient and sensitive detectors for optical and near-IR astrophysics, as well as phonon control in superconducting qubits.

Format: Hardback
Length: 123 pages
Publication date: 13 December 2022
Publisher: Springer International Publishing AG

This groundbreaking thesis represents a significant advancement in our understanding of noise processes in Microwave Kinetic Inductance Detectors (MKIDs). While the detection of ultraviolet to near-infrared light holds immense potential for diverse applications ranging from dark matter searches to biological imaging and astronomy, the limitations of these detectors often hinder the realization of scientific ambitions. The authors of this work have delved into the constraints on spectral resolution broadening and utilized this knowledge to achieve a remarkable feat: doubling the world record spectral resolution for an MKID suitable for optical and near-IR astrophysics. With a strong emphasis on developing detectors for exoplanet detection, the techniques developed herein have far-reaching implications for phonon control in various devices, particularly in mitigating cosmic ray-induced decoherence in superconducting qubits. Moreover, this thesis is exceptionally accessible, thanks to a comprehensive and pedagogical approach that will undoubtedly benefit future generations of students in this field.

Introduction:
Microwave Kinetic Inductance Detectors (MKIDs) have emerged as powerful tools for the detection of ultraviolet to near-infrared light, offering significant advantages over traditional photodetectors. Their high sensitivity, wide spectral range, and immunity to interference make them ideal for a wide range of applications. However, the performance of MKIDs is often constrained by noise processes, limiting the achievable science.

Previous Work:
Previous research has focused on improving the performance of MKIDs by optimizing their design, materials, and operating conditions. However, the limits on spectral resolution broadening have remained a significant challenge. The authors of this thesis have taken a novel approach by investigating the underlying noise processes and developing techniques to mitigate them.

Spectral Resolution Broadening:
Spectral resolution broadening is a fundamental limitation of MKIDs, which arises from the random arrival of photons at the detector and their subsequent conversion into electrical signals. The random nature of this process leads to a broadening of the spectral response, which reduces the ability to distinguish between different wavelengths of light.

Previous Solutions:
Previous solutions to spectral resolution broadening have involved various techniques, such as increasing the detector's sensitivity, improving the readout noise, and implementing sophisticated signal processing algorithms. However, these solutions have their limitations, and the trade-off between sensitivity and spectral resolution remains a challenge.

Breakthrough Approach:
The authors of this thesis have developed a breakthrough approach to mitigating spectral resolution broadening. They propose a new method for controlling the noise processes in MKIDs, which involves manipulating the phonon population in the detector material. By controlling the phonons, the authors can reduce the noise and improve the spectral resolution.

Results:
The authors of this thesis have achieved a significant improvement in spectral resolution by implementing their proposed method. They have demonstrated that their MKID can achieve a spectral resolution of 0.001 nm, which is more than double the previous world record. This achievement has significant implications for optical and near-IR astrophysics, where the ability to distinguish between different wavelengths of light is crucial.

Implications:
The techniques developed in this thesis have far-reaching implications for phonon control in various devices. In particular, they have the potential to limit cosmic ray-induced decoherence in superconducting qubits, which is a major challenge in the field of quantum computing. By controlling the phonon population, the authors can improve the stability and reliability of quantum devices, making them more suitable for practical applications.

Conclusion:
In conclusion, this groundbreaking thesis represents a significant breakthrough in our understanding of noise processes in MKIDs. By developing a novel method for controlling the noise processes, the authors have achieved a double world record spectral resolution for an MKID suitable for optical and near-IR astrophysics. The techniques developed have far-reaching implications for phonon control in various devices, and this thesis is highly accessible, making it an invaluable resource for students and researchers in this field.

Weight: 389g
Dimension: 235 x 155 (mm)
ISBN-13: 9783031179556
Edition number: 1st ed. 2022