"a challenging field" is correct and usable in written English.
You can use it to describe any area of work or study that requires significant effort. For example, "Computer programming is a challenging field, but it's also incredibly rewarding."
Autonomous robotic navigation based on machine vision, presents a challenging field in current robotics research.
The localization of mobile systems with video data is a challenging field in robotic vision research.
However, the complete and predictable reconstruction of healthy periodontal tissues still remains a challenging field.
Hypospadias is a challenging field of urogenital reconstructive surgery, with different techniques currently being used.
Multiple-target tracking is a challenging field specially when dealing with uncontrolled scenarios.
However, the development of an efficient imaging chemosensor of H2S in live animals is a challenging field for chemists.
It is a challenging field because of the unique physical chemical properties of materials at the nanoscale.
Although transplant biology remains a challenging field, xenotransplantation has the potential to help doctors provide transplants to more of the many waitlisted patients who desperately need them.
Behavior genetics is a particularly challenging field for making a clear-cut case that mouse experiments work, because researchers believe that both the phenomena they are studying and the animal models they are using are complex.
Sometimes it results in a lifelong drive to succeed in a highly challenging field.
It is also a very challenging field, demanding increasingly broad but also deep training and an ever more interdisciplinary approach.
