[9a-A24-1~12] 11.3 Analog applications and their related technologies

10:15 AM - 10:30 AM JST(1:15 AM - 1:30 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation Award

[9a-A24-6] Structural Optimization of Submillimeter MKIDs for Noise Reduction

〇Taiki Sato¹, Akihide Koyama², Shinsuke Uno³, Satoru Mima⁴, Tatsuya Takekoshi⁵, Tai Oshima⁶, Tohru Taino¹ (1.Saitama Univ., 2.UEC., 3.RIKEN., 4.NICT., 5.KIT., 6.NAOJ.)

Keywords:

MKID,Millimeter-wave and submillimeter-wave observations,Greenland Telescope

Resolving the tensions in the standard cosmological model requires reducing systematic errors in galaxy cluster mass estimation. To this end, we are developing GLTCAM, a wide-field six-band millimeter/submillimeter camera for the Greenland Telescope, to observe distant galaxy clusters. Detecting their faint signals requires long integration, where the 1/f two-level-system (TLS) noise of microwave kinetic inductance detectors (MKIDs) becomes a limiting factor. To reduce TLS noise through structural optimization, we fabricated lumped-element MKIDs with interdigital capacitors (IDCs), reported to suppress TLS noise, alongside conventional distributed-element MKIDs on the same chip, using both Nb and TiN. We measured their noise characteristics at 240 mK using a frequency-multiplexed readout. We report the design, fabrication, and cryogenic measurement results, and discuss the dependence of TLS noise on the IDC line parameters.