可以这样设置
xlabel('\itx','Fontname','Times New Roman')
搜索matlab help中的 text properties
\bf — Bold font
\it — Italic font
\sl — Oblique font (rarely available)
\rm — Normal font
\fontname{fontname} — Specify the name of the font family to use.
\fontsize{fontsize} — Specify the font size in FontUnits.
\color(colorSpec) — Specify color for succeeding characters
_和^用于下标和上标
如果需要显示_ ^ { }这些特殊字符，在前面加\，例如 \\, \{, \} \_,\^.
The subscript character "_"and the superscript character "^"modify the character or substring defined in braces immediately following.
To print the special characters used to define the TeX stringswhen Interpreter is Tex, prefixthem with the backslash "\" character: \\, \{, \} \_,\^.