Sympathetic cooling of a large <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si88.svg" display="inline" id="d1e1135"><mml:mrow><mml:msup><mml:mrow /><mml:mrow><mml:mn>113</mml:mn></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mi mathvariant="normal">Cd</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math> ion crystal with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si90.svg" display="inline" id="d1e1151"><mml:mrow><…

We have sympathetically cooled and crystallized 113Cd+ ions with laser-cooled 40Ca+ ions, directly observed the complete large bicrystal structure in a linear Paul trap. The two-component crystal contains up to 3.5×103 6.8×103 ions. temperature of was measured be as low 41 mK mass ratio, which is twice that our previous work. Based on obtained work, we further studied several properties structures ultracold sample. factors affecting sympathetic cooling effect were studied, including electrical parameters number ratio between sympathetically-cooled results this paper enrich experimental research ion crystals, sample makes it possible improve accuracy cadmium-ion microwave frequency standard.