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arXiv · 2512.04347

Theoretical analysis of frequency variation tolerance between elements of RTD-THz oscillator arrays for mutual locking

Masahiro Asada·Safumi Suzuki
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Abstract

Array configuration is one of the effective ways to increase the output power of terahertz oscillators using resonant tunneling diodes. Mutual locking between the array elements results in coherent single-spectrum oscillation and a narrow radiation beam. However, frequency variation between elements disturbs the mutual locking. In this paper, the frequency variation that can be tolerated for mutual locking is approximately derived for an array with arbitrary coupling configuration. Using this result, the element-number dependence of the frequency variation tolerance for 1D and 2D arrays is calculated. In 1D arrays, the frequency variation tolerance decreases inversely proportional to the square root of the element number. In 2D arrays, as the number of columns is increased while keeping the number of elements per column constant, the frequency variation tolerance increases for small number of columns, reaches a maximum at square configuration, and then decreases with increasing number of columns. The element-number dependence in 2D arrays is smaller than that in 1D arrays.

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Masahiro Asada, Safumi Suzuki. 2025-12-04. Theoretical analysis of frequency variation tolerance between elements of RTD-THz oscillator arrays for mutual locking. https://arxiv.org/abs/2512.04347

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