Red quantum dot, light emitting material and manufacturing method of quantum dot

A red quantum dot, comprising an outer shell and an inner core from outside in, wherein the outer shell covers a surface of the inner core,

• wherein a wavelength of a light emitted by the red quantum dot ranges from 610 nm to 660 nm,
• the red quantum dot has a ratio of an emission intensity to an absorption intensity of the red quantum dot at a characteristic wavelength ranges from 1.5×108 CPS/Abs. to 2.0×109 CPS/Abs., wherein the characteristic wavelength is a shorter wavelength of two wavelengths corresponding to half of a maximum intensity of an emission peak of the red quantum dot,
• wherein the inner core consists essentially of at least one element selected from the group consisting of zinc, cadmium, mercury, aluminum, gallium, indium, tin, and lead, and at least one element selected from the group consisting of arsenic, selenium, and tellurium.