正入射侧入射移动

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2025-10-27 19:05:14 +08:00
parent 6fd9ccfa95
commit 0275960571
9 changed files with 46 additions and 37 deletions

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@@ -57,4 +57,26 @@ todo
散射光路对不同偏振的响应不同,因此需要乘以一个系数。
探索为什么对于A1的拟合结果会差两倍
探索为什么对于A1的拟合结果会差两倍
E#sub[1]-1 模式在正入射拉曼实验中被观察到尽管在理论上是不允许的这被认为是因为入射光并非完全沿c轴入射。
如图所示由于非零的数值孔径激光汇聚到样品上时存在一个锥形角度不完全平行于c轴使得 E#sub[1]-1 模式在正入射中总是可见的。
由于衬底斜切沿着x方向对于 zxxz zxyz 配置,入射光或散射光的偏振将具有更多的 z 分量,从而使 E#sub[1]-1 模式的强度增加。
通过略微倾斜衬底可以补偿斜切导致的效应,如附图所示。
同时,此对比也可以验证衬底斜切的方向。
Two effects beyond ideal theoretical prediction were observed experimentally,
including minor but observable peak shifts of negligible-polar phonons between different incidence configurations,
and the observability of the E#sub[1]-1 mode in normal incidence Raman experiments.
The peak shifts were considered caused by the non-zero wavevector lengths of phonons.
In our calculations, compared to normal incidence,
the E#sub[2]-3 mode's frequency remained nearly unchanged,
while the E#sub[2]-1, E#sub[2]-2, A#sub[1]-1 modes exhibited minor but observable shifts.
The experimental results were in good agreement with our calculations, as shown in figure and table.
The visibility of the E#sub[1]-1 mode in normal incidence Raman experiments were attributed to the fact that
the incident light was not perfectly aligned along the z-axis,
due to the substrate's slight tilt and the converging angle of the confocal setup.
This was confirmed by the results under different polarization configurations and different tilt angles,
as shown in figure.
#include "figure-e1.typ"

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@@ -87,31 +87,20 @@ Our experiments reported the E#sub[1]-2 peak for the first time,
#include "figure-raman.typ"
E#sub[1]-1 模式在正入射中可见
不同入射方向下有微小移动
E#sub[1]-1 模式在正入射拉曼实验中被观察到尽管在理论上是不允许的这被认为是因为入射光并非完全沿c轴入射
如图所示由于非零的数值孔径激光汇聚到样品上时存在一个锥形角度不完全平行于c轴使得 E#sub[1]-1 模式在正入射中总是可见的。
由于衬底斜切沿着x方向对于 zxxz zxyz 配置,入射光或散射光的偏振将具有更多的 z 分量,从而使 E#sub[1]-1 模式的强度增加。
通过略微倾斜衬底可以补偿斜切导致的效应,如附图所示。
不同入射方向下弱极性峰位的微小移动被观察到,这是由于非零波矢长度的声子引起的。
为了检验我们实验和计算的准确性,我们测量和计算了不同入射方向下弱极性峰位的微小移动
在我们的计算中从正入射到肩入射E2-3的峰位几乎不变E2-1与A1-1会有可观测的蓝移同时E2-2会有可观测的红移。
实验结果与计算结果基本一致,如图如表所示。
Some effects absent in previous theory were observed experimentally,
including minor but observable peak shifts of negligible-polar phonons between different incidence configurations,
and the observability of the E#sub[1]-1 mode in normal incidence Raman experiments.
The peak shifts were considered caused by the non-zero wavevector lengths of phonons.
In our calculations, compared to normal incidence,
the E#sub[2]-3 mode's frequency remained nearly unchanged,
while the E#sub[2]-1, E#sub[2]-2, A#sub[1]-1 modes exhibited minor but observable shifts.
The experimental results were in good agreement with our calculations, as shown in figure and table.
The visibility of the E#sub[1]-1 mode in normal incidence Raman experiments were attributed to the fact that
the incident light was not perfectly aligned along the z-axis,
due to the substrate's slight tilt and the converging angle of the confocal setup.
This was confirmed by the results under different polarization configurations and different tilt angles,
as shown in figure.
To further validate the accuracy of our experiments and calculations,
we measured and calculated the peak shifts of negligible-polar phonons
under different incidence configurations.
In our calculations, comparing with normal incidence,
the E#sub[2]-3 peek remained nearly unchanged under edge incidence (only shifted about 0.004 cm#super[-1]),
thus we use it as a reference to calibrate other peak positions.
The E#sub[2]-1, E#sub[2]-2, and A#sub[1]-1 modes exhibited observable shifts,
and the experimental results were in good agreement with our calculations, as shown in figure and table.
Our results further confirmed the accuracy of both our experiments and calculations.
#include "figure-nopo-diff.typ"
#include "figure-e1.typ"

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@@ -1,12 +1,7 @@
#figure(
image("/画图/弱极性不同方向偏移/embed.svg"),
image("/画图/弱极性不同方向偏移/拉曼.svg"),
caption: [
(a) Phonon dispersion of 4H-SiC along the A#sym.GammaK high-symmetry path.
Gray lines represent negligible-polar phonon modes,
while colored lines indicate strong-polar phonon modes.
(b) Magnified view of the boxed region in (a).
The orange dashed lines mark the phonon wavevectors involved in Raman scattering
with incident light along the z- and y-directions.
Frequency shifts of negligible-polar phonon modes under different incidence configurations.
],
placement: none
)<fig-nopo-diff>

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@@ -55,7 +55,7 @@
* 251019:
* 1: 衬底侧入射 xzyx 观察 E12 离焦 0 针孔 100 积分时间 30 积分次数 10 范围 600-790 5 个点
* 2: 正入射衬底将zxxz稍微垫高一点的结果。垫高x方向的某个方向。先分别测试不垫高和垫高的结果确认有明显差别后再多测试几个点。
* 3: 衬底正入射,离焦 0 针孔 100 积分时间 5 积分次数 10 范围 580-10501 是衬底,其余依次是 532 631 230 126 206 取 11 个点。
* 3: 外延层正入射,离焦 0 针孔 100 积分时间 5 积分次数 10 范围 580-10501 是衬底,其余依次是 532 631 230 126 206 取 11 个点。
* 2510xx:
* 1: 正入射衬底将zxxz稍微垫高一点的结果。垫高x方向的某个方向。
* 2: 外延层侧入射。