<p>We performed a simulation study on resonant tunneling diodes (RTDs) with auxiliary wells (emitter prewell, center subwell, and collector postwell) using self-consistent solutions based on a Wigner–Poisson equation. We previously performed a simulation study on RTDs with auxiliary wells using the Wigner transport equation within the framework of the flat-band model. The flat-band model has a major limitation in that it neglects Coulomb interactions and employs linear potential profiles as input to the Wigner transport equation. The present study reassesses the performance of RTDs with auxiliary wells using the self-consistent solutions instead of the flat-band model. The main findings of this study are summarized as follows. As the prewell width increases, the peak voltage (<InlineEquation ID="IEq1"> <EquationSource Format="TEX">$V_\textrm{p}$</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>V</mi> <mtext>p</mtext> </msub> </math></EquationSource> </InlineEquation>) increases for widths below 5 nm, whereas a further increase beyond 5 nm leads to a reduction in <InlineEquation ID="IEq2"> <EquationSource Format="TEX">$V_\textrm{p}$</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>V</mi> <mtext>p</mtext> </msub> </math></EquationSource> </InlineEquation>. In contrast, increasing the subwell width consistently decreases <InlineEquation ID="IEq3"> <EquationSource Format="TEX">$V_\textrm{p}$</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>V</mi> <mtext>p</mtext> </msub> </math></EquationSource> </InlineEquation>. Both the prewell and the subwell made clear contributions to the increase in PVR (peak-to-valley current ratio), and the prewell was more effective than the subwell in improving the PVR. RTDs with both a prewell and a subwell achieved a greater improvement in PVR compared to RTDs with only one auxiliary well. Calculations for an RTD with appropriately chosen prewell and subwell widths yielded an optimal PVR value. The postwell yielded a higher PVR compared to the RTD without auxiliary wells, but lower than those achieved with the prewell or subwell. In addition, variations in the postwell width did not produce any significant effect on the PVR.</p>

A simulation study on resonant tunneling diodes with auxiliary quantum wells based on a self-consistent Wigner–Poisson equation

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发表日期：

2026年3月24日

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Joon-Ho Lee,
Joonho Park,
Dongyel Kang

摘要

We performed a simulation study on resonant tunneling diodes (RTDs) with auxiliary wells (emitter prewell, center subwell, and collector postwell) using self-consistent solutions based on a Wigner–Poisson equation. We previously performed a simulation study on RTDs with auxiliary wells using the Wigner transport equation within the framework of the flat-band model. The flat-band model has a major limitation in that it neglects Coulomb interactions and employs linear potential profiles as input to the Wigner transport equation. The present study reassesses the performance of RTDs with auxiliary wells using the self-consistent solutions instead of the flat-band model. The main findings of this study are summarized as follows. As the prewell width increases, the peak voltage ( $V_\textrm{p}$ $V_{p}$ ) increases for widths below 5 nm, whereas a further increase beyond 5 nm leads to a reduction in $V_\textrm{p}$ $V_{p}$ . In contrast, increasing the subwell width consistently decreases $V_\textrm{p}$ $V_{p}$ . Both the prewell and the subwell made clear contributions to the increase in PVR (peak-to-valley current ratio), and the prewell was more effective than the subwell in improving the PVR. RTDs with both a prewell and a subwell achieved a greater improvement in PVR compared to RTDs with only one auxiliary well. Calculations for an RTD with appropriately chosen prewell and subwell widths yielded an optimal PVR value. The postwell yielded a higher PVR compared to the RTD without auxiliary wells, but lower than those achieved with the prewell or subwell. In addition, variations in the postwell width did not produce any significant effect on the PVR.