This work examines charge ${\mathrm{\Delta }}_T$ noise in two-terminal hybrid nanostructures featuring a quantum point contact (QPC), realized either between two normal metallic leads (NQN) or between a normal metal and a superconducting lead (NQS). The energy-dependent transmission of a QPC breaks electron-hole (e-h) symmetry, leading to a finite thermovoltage under an applied temperature and voltage bias. In contrast, in earlier studies on hybrid junctions incorporating insulating barriers, as electron-hole symmetry is preserved, have vanishing thermovoltage, and consequently, charge ${\mathrm{\Delta }}_T$ noise is calculated at zero thermovoltage. In our setup, the broken e-h symmetry allows for a finite thermovoltage, at which we compute the corresponding charge ${\mathrm{\Delta }}_T$ noise. Unlike earlier studies restricted by electron-hole symmetry and vanishing thermovoltage, our work establishes a self-consistent thermoelectric noise framework in mesoscopic hybrid junctions, revealing how Andreev reflection fundamentally reshapes charge ${\mathrm{\Delta }}_T$ noise once electron-hole symmetry is broken. This broad access to charge fluctuation signatures provides a more comprehensive understanding of nonequilibrium transport in linear response. To the best of our knowledge, this is the first work that systematically explores the interplay between Andreev reflection and electron-hole symmetry breaking in the context of quantum noise and ${\mathrm{\Delta }}_T$ noise in mesoscopic hybrid structures.

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• Shot noise
• Point contacts
• Superconductors