The ballistic orbital current $\left(J_L\right)$ promises more efficient information transfer over longer distances in various materials compared with spin current $\left(J_S\right)$. However, experimental observation and quantitative investigation of ballistic orbital transport remain elusive due to the entanglement between $J_L$ and $J_S$. Here, we show that the vanishingly small spin-orbit coupling of Cu and its negligible $d$-orbital character close to the Fermi energy allow spin-independent orbital investigation. Combined with theoretical and experimental results, we reveal that the ballistic transport length of $J_L$ generated by Cr reaches up to 13 nm, a magnitude larger than the typical spin-diffusion length of 1–2 nm. Moreover, an orbital efficiency of 0.44 was quantitatively determined in Cr, which is 1.9 times larger than that of spin-dominated heavy metal Pt. These results not only provide a convenient approach for the quantitative study of $J_L$ but also highlight the significant potential of orbital engineering in spin-orbitronics applications.

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• Spin Hall effect
• Spin diffusion
• Spin generation
• Spin relaxation
• Spin-orbit torque
• Spintronics
• Metals
• Methods in transport
• Transport techniques