如何在matplotlib中更改科学符号的字体大小?

我想绘制一个大字体的图，我可以轻松更改所有字体大小，除非在轴标签中使用科学记数法.我已经搜索并尝试过，但是还没有找到改变科学附录大小的方法.看到这个图:

I want to make a plot with large font size, I can change all font sizes easily except when I use scientific notations in the axis label. I have searched and tried but haven't found a way to change the size of the scientific appendix. See this figure:

在此图中，"1e-4"与其他文本和标签相比太小了. 这些代码与生成此图中使用的放大字体有关:

In this figure, "1e-4" is just too small compared to other texts and labels. These codes are relevant in producing the enlarged fonts used in this figure:

ax.tick_params(labelsize=24)
ax.yaxis.get_major_formatter().set_powerlimits((0, 1))
ax.text(0.3,4.9e-4,'(a)',va='top',fontsize=24)
plt.xlabel('$r$ (a.u.)',fontsize=24)
plt.ylabel('Probability',fontsize=24)

顺便说一句，如何将"1e-4"更改为"x1e-4"?谢谢！

By the way, how to change "1e-4" into "x1e-4"? Thanks!