arXiv subjects

Gulzat Jaliel

Publications and source records attributed to Gulzat Jaliel.

4 recordsLinked to original sources

arXiv2026

SiMOS quantum-dot spin qubits enabled by extreme-ultraviolet lithography

The realization of large-scale silicon quantum processors requires spin qubits compatible with advanced semiconductor manufacturing technologies, demanding lithographic processes that combine nanometer-scale precision with exceptional uniformity. Although the highest-performing silicon spin qubits demonstrated to date have relied on electron-beam (e-beam) lithography, its serial exposure process limits reproducibility studies and wafer-scale fabrication. Here, we demonstrate high-performance silicon metal-oxide-semiconductor (SiMOS) spin qubits fabricated using extreme-ultraviolet (EUV) lithography in a 300 mm semiconductor pilot line. We report wafer-scale quantum-dot uniformity metrics, including 100 % room-temperature gate-to-gate leakage yield and sub-nanometer control of critical gate dimensions. We characterize four double-dot systems realized in two triple-quantum-dot devices. Gate set tomography (GST) reveals consistently high fidelities across all four systems, with values up to 99.8 % for SPAM, 99.9 % for single-qubit gates, and 99.1 % for two-qubit gates. The devices exhibit highly reproducible exchange turn-on characteristics of 10-13 dec/V, indicating high fabrication uniformity enabled by EUV patterning. These results establish EUV lithography as a viable manufacturing technology for quantum processors based on high-fidelity SiMOS spin qubits.

cond-mat.mes-hall↗

arXiv2026

Understanding oxide-thickness-dependent variability in dense Si-MOS quantum dot arrays

Achieving uniform and scalable control of semiconductor spin qubits remains a key challenge for large scale quantum computing. In this work, we investigate how gate oxide thickness influences uniformity in dense two dimensional silicon quantum dot arrays. Using a 7 x 7 array fabricated in a 300 mm CMOS-process patterned by EUV lithography, we statistically characterize 392 quantum dots across four different oxide thicknesses. The threshold voltages, capacitances, lever arms, and charging energies are extracted using parallel row based measurements and we identify an optimal SiO2 thickness of 17 nm that minimizes threshold voltage variability below 63 mV standard deviation. Our observations illustrate how multiple sources of disorder can introduce competing oxide-thickness dependencies, resulting in non-monotonic trends. These results provide key design guidelines for dense, scalable silicon spin qubit architectures.

quant-ph↗

arXiv2025

Long coherence silicon spin qubit fabricated in a 300 mm industrial foundry

Silicon spin qubits offer long coherence times, a compact footprint and compatibility with industrial CMOS manufacturing. Here, we investigate spin qubits hosted in quantum dots fabricated in a state-of-the-art 300 mm nanoelectronics foundry and demonstrate substantially enhanced coherence, achieving a Hahn-echo time of $T_2^{\text{Hahn}} = 4\,\mathrm{ms}$ for singlet--triplet oscillations. Employing noise spectroscopy and noise correlation measurements, we identify detuning noise with an amplitude of $\delta \varepsilon_{\mathrm{rms}} = 2.2\,\mu\mathrm{eV}$ (integrated over 90 s) and observe strong zero-phase correlations between two spatially separated spin qubits. The singlet--triplet basis intrinsically rejects these common-mode fluctuations, yielding a pronounced suppression of dephasing. Our results suggest that exploiting the versatility of silicon quantum dots to adapt the qubit encoding to the microscopic noise landscape represents a promising strategy for advancing scalable quantum information processing.

cond-mat.mes-hall↗

arXiv2023

Identifying Many-Body Localization in Realistic Dot Arrays

We determine whether or not it is possible to identify many-body localization in quantum dot arrays, given their current technological capacities. We analyze the phase diagram of an extended Fermi-Hubbard model - a theoretical system that quantum dot arrays are known to simulate - using several quantities of varying experimental accessibility. By deriving the parameters of our model from our experimental system, we find that many-body localization can potentially be detected in current-generation quantum dot arrays. A pitfall that we identify is that the freezing of a system due to strong interactions yields signatures similar to conventional localization. We find that the most widely-used experimental signature of localization - the imbalance - is not sensitive to this fact, and may be unsuitable as the lone identifier of the many-body localized regime.

cond-mat.dis-nn↗