arXiv subjects

Rosdisham Endut

Publications and source records attributed to Rosdisham Endut.

3 recordsLinked to original sources

arXiv2026

Quantum Otto machine with $q$-deformed Pöschl-Teller oscillator

We study the impact of the potential parameters of the q-deformed modified Pöschl-Teller potential on the thermodynamic performance of a quantum Otto cycle, where the $q$-deformed modified Pöschl-Teller potential serves as the working substance. Analytical expressions for the energy spectrum and wave functions are derived, enabling a systematic investigation of heat exchange, work output, efficiency, and coefficient of performance. We show that $q$-deformation modifies the energy spectrum and creates distinct performance regions in the ($q$, $Δ$) parameter space. Low ($Δ$) and high ($q$) favour optimal heat engine efficiency, whereas high ($Δ$) and low ($q$) improve refrigerator performance. The heat engine efficiency peaks in the low-($Δ$), high-($q$) regime. These results highlight the q-deformed modified Pöschl-Teller potential as a versatile and tunable platform for exploring potential parameter-driven effects in quantum thermal machines.

quant-ph↗

arXiv2026

Hardware-Free Polarization Stabilization for Measurement-Device-Independent Quantum Key Distribution via Correlated Twirling

Measurement-Device-Independent Quantum Key Distribution (MDI-QKD) provides unconditional security against detector vulnerabilities, but its practical deployment is severely hindered by asymmetric channel turbulence. Fluctuations in optical fibers induce arbitrary polarization drift, degrading Hong-Ou-Mandel interference and forcing extensive calibration downtime. In this work, we propose a hardware-free polarization stabilization technique utilizing a Correlated Twirling protocol based on a unitary 2-design. By applying a synchronized, public twirling supermap, Alice and Bob mathematically transform deterministic, asymmetric geometric rotations into an isotropic Pauli depolarizing channel. Executed entirely as a virtual post-processing step during classical sifting, this protocol mathematically suppresses intrinsic channel noise by a factor of 2/3. We demonstrate through exact quantum state simulations that this induced symmetry neutralizes catastrophic axis-dependent failures, extending the Y-bias tolerance from 0.68 to 0.84 radians. Furthermore, the protocol passively extends the absolute angular misalignment tolerance for the 11% security threshold from $38.7^\circ$ to $47.9^\circ$, sustaining secure key distillation over extended fiber distances in highly turbulent regimes where standard architectures fail. Inherently compatible with decoy-state weak coherent pulses, this algorithmic approach provides a highly scalable, resource-efficient framework for robust long-distance quantum networks.

quant-ph↗

arXiv2025

Fisher Information Measures under Lattice Combined Paul Trap

We examine how the informational properties of a confined single ion response in a Paul trap modified by optical-lattice. We focus on the ground and first excited motional states and show that Fisher information, Shannon entropy, and Fisher-Shannon complexity track the effective frequency $\omega_{\mathrm{eff}}=\omega\sqrt{1-\kappa}$ of the potential. We show that the Fisher information and Shannon entropy reflect an effective frequency-driven redistribution of information between conjugate spaces. Our results show that the Fisher-Shannon complexity measure remains invariant under effective frequency control. The invariance demonstrates that optical modulation of $\kappa$ rescales localization, without altering the harmonic structure of the motional states. These results establish a controlled information-theoretic baseline for lattice-assisted Paul traps. Beyond the harmonic limit, retaining the quartic lattice correction introduces non-Gaussian wavefunction features through state-dependent mixing of higher eigenstates, which breaks the mutual compensation between Fisher information and Shannon entropy that sustains the invariant. The departure of $P'$ from its harmonic reference value intensifies with $\kappa$ and is stronger for the excited state, which confirms that the Fisher-Shannon complexity invariance is a distinctive property of the small-oscillation harmonic regime.

quant-ph↗