BUSCADOR RECOLECTA

In this paper, a W-band 3D-printed bandpass filter is proposed. The use of higherorder TE10n modes in groove gap waveguide (GGW) technology is evaluated in order to alleviate the manufacturing requirements. In addition to the use of higherorder modes, the coupling between them is analyzed in detail to improve the overall fabrication robustness of the component. This allows the implementation of narrowband filters operating at millimeter-wave frequency bands (or above), which usually demand complex manufacturing techniques to provide the high accuracy required for this kind of devices. In order to show the applicability of the proposed method, a narrow-band 5th-order Chebyshev bandpass filter centered at 94 GHz, which can be easily fabricated by state-of-the-art stereolithographic (SLA) 3D-printing techniques followed by silver coating, is shown. Excellent measured performance has been obtained.

We propose a novel experiment, the Canfranc Axion Detection Experiment (CADEx), to probe dark matter axions with masses in the range 330–460 μeV, within the W-band (80–110 GHz), an unexplored parameter space in the well-motivated dark matter window of Quantum ChromoDynamics (QCD) axions. The experimental design consists of a microwave resonant cavity haloscope in a high static magnetic field coupled to a highly sensitive detecting system based on Kinetic Inductance Detectors via optimized quasi-optics (horns and mirrors). The experiment is in preparation and will be installed in the dilution refrigerator of the Canfranc Underground Laboratory. Sensitivity forecasts for axion detection with CADEx, together with the potential of the experiment to search for dark photons, are presented., SA and JM are supported by grants PID2019-108122GB-C32 and the Maria de Maeztu grant CEX-2019-000918-M of ICCUB. The work of UPCTand IFIC is supported by grant PID2019-108122GB-C33, funded by MCIN/AEI/10.13039/501100011033/ and by “ERDF A way of making Europe”. JMGB thanks the grant FPI BES-2017-079787, funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”. The work of Universidad de Cantabria is supported by the Ministry of Science and Innovation under Grant PID2019-110610RB-C22. CAB and IMDEA-Nanoscience work is supported by grants PID2019-105552RB-C41 and PID2019-105552RB-C44 and by Comunidad de Madrid under Grant P2018/NMT-4291. IMDEA-Nanoscience acknowledges financial support from “Severo Ochoa” Programme for Centers of Excellence in R&D (MINECO, Grant SEV-2016-0686). D.G. and A.G also acknowledge Grant DEFROST N62909-19-1-2053 from ONR Global. RBB, FJC, BJK, EMG, JMS and PV thank the Spanish Agencia Estatal de Investigación (AEI, MICIU) for the support to the Unidad de Excelencia María de Maeztu Instituto de Física de Cantabria, ref. MDM-2017-0765. RBB, FJC, EMG and PV thank the Spanish Agencia Estatal de Investigación (AEI, MCI) for the funds received through the research project, ref. PID2019-110610RB-C21. RBB, FJC, BJK, EMG, JMS and PV also thank the ‘Dark Collaboration at IFCA’ working group for useful discussions. The work done by ANTERAL S.L. is supported by project QON-Space financed by the Navarra Government Project No. 0011-1365-2021-000220. UPNA acknowledges financial support from the Spanish State Research Agency, Project No. PID2019-109984RB-C43/AEI/10.13039/501100011033 and Project No. PID2020-112545RB-C53/MCIN/AEI/ 10.13039/501100011033., Peer reviewed