This study focuses on Catalan cabinet ministers in democratic Spain with a view to understanding what function they perform in the central government: regional ambassador or state agent? To this end, this analysis draws on a sub-dataset comprised of 22 Catalan cabinet ministers taken from a general pool of 220 cabinet ministers and 371 ministerial appointments from 1977 to 2021. Our findings demonstrate, first, that no Catalan cabinet minister has ever reached the position of Prime Minister and Catalans constitute a kind of ministerial “middle class” occupying intermediate positions in the cabinet. Second, the examination of career paths and publications of Catalan ministers shows that their role varied according to circumstances. Third, in this article we argue that those variations can be best interpreted as a delegation between principal and agent relying on two main variables, namely the type of party they belong to in Catalonia and the parliamentarian majority sustaining the party controlling the Spanish cabinet.

The epitaxial integration of III–V optoelectronic devices on silicon will be the enabling technology for full-scale deployment of silicon photonics and the key to improving communication systems. Silicon photonics also offer new opportunities for the realization of ultracompact and fully integrated sensing systems operating in the mid-infrared (MIR) regime of the spectrum. In this article, we review recent developments, through several approaches, in the direct metamorphic epitaxial growth of various III–V materials-based lasers on silicon substrates. We show that GaAs-based 1.3-μm III–V quantum dot lasers and GaSb-based MIR quantum-well lasers grown on silicon substrates can operate with low threshold current density and high operating temperature, which hold promise for the future.

Mid-wavelength infrared (MWIR) avalanche photodiodes (APDs) were fabricated using Indium Arsenide- Gallium Antimonide (InAs-GaSb) based strain layer superlattice (SLS) structures. They were engineered specifically to have either electron or hole dominated ionization. The gain characteristics and the excess noise factors were measured for both devices. The electron dominated p+-n−-n APD with a cut-off wavelength of 4.13 μm at 77 K had a maximum multiplication gain of 1800 measured at -20 V while that of the hole dominated n+-p--p structure with a cut-off wavelength of 4.98 μm at 77 K was 21.1 at -5 V at 77 K. Excess noise factors were measured between 1-1.2 up to a gain of 800 and between 1-1.18 up to a gain of 7 for electron and hole dominated APDs respectively.