Mesoscopic interference for metric and curvature & gravitational wave detection. (6th August 2020)

• Record Type: Journal Article
• Authors: Marshman, Ryan J; Mazumdar, Anupam; Morley, Gavin W; Barker, Peter F; Hoekstra, Steven; Bose, Sougato
• Is Part Of: New journal of physics. Volume 22:Number 8(2020:Aug.)
• Publication Date: 2020-08-06
• Subjects: Stern–Gerlach interferometry -- general relativity -- gravitational waves; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/ab9f6c
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: A compact detector for space-time metric and curvature is highly desirable. Here we show that quantum spatial superpositions of mesoscopic objects could be exploited to create such a detector. We propose a specific form for such a detector and analyse how asymmetries in its design allow it to directly couple to the curvature. Moreover, we also find that its non-symmetric construction and the large mass of the interfered objects, enable the detection gravitational waves (GWs). Finally, we discuss how the construction of such a detector is in principle possible with a combination of state of the art techniques while taking into account the known sources of decoherence and noise. To this end, we use Stern–Gerlach interferometry with masses ∼10 −17 kg, where the interferometric signal is extracted by measuring spins and show that accelerations as low as 5 × 10 −15 ms −2 Hz −1/2, as well as the frame dragging effects caused by the Earth, could be sensed. The GW sensitivity scales differently from the stray acceleration sensitivity, a unique feature of the proposed interferometer. We identify mitigation mechanisms for the known sources of noise, namely gravity gradient noise, uncertainty principle and electro-magnetic forces and show that it could potentially lead to a metre sized, orientable and vibrational noise (thermal/seismic) resilient detector of mid (ground based) and low (space based) frequency GWs from massive binaries (the predicted regimes are similar to those targeted by atom interferometers and LISA).