In this talk, I focus on our development of engineered environments
for quantum-mechanically behaving superconducting circuits. In this
context, I present our recent results on quantum-limited heat
conduction over macroscopic distances [1] and on the quantum circuit
refrigerator. In the future, we aim to develop these concepts further
into in-situ-tunable components that can be use to conveniently cool
down electric quantum devices at will, although not hindering their
coherent operation when desired. Such components can potentially be
applied in the initialization of quantum registers in a gate-based
quantum computer and in the enhancement quantum annealers. Finally, I
introduce a thermal detector for propagating microwave photons [2] and
demonstrate that it can achieve energy resolution of a single
zeptojoule using electrothermal feedback [3]. To our knowledge, this
is an order-of-magnitude improvement over previous thermal detectors,
paving the way for high-fidelity single-photon microwave detectors.


[1] M. Partanen et al. Nature Phys. 12, 460 (2016).
[2] J. Govenius et al. Phys. Rev. B 90, 064505 (2014).
[3] J. Govenius et al. arXiv:1512.07235 (2015).